Problem:
 Score : 300 points    Problem Statement We have a string X , which has an even number of characters. Half the characters are S , and the other half are T .  Takahashi, who hates the string ST , will perform the following operation 10^{10000} times:   Among the occurrences of ST in X as (contiguous) substrings, remove the leftmost one. If there is no occurrence, do nothing.   Find the eventual length of X .      Constraints  2 ≦ |X| ≦ 200,000  The length of X is even.  Half the characters in X are S , and the other half are T .       Partial Scores  In test cases worth 200 points, |X| ≦ 200 .         Input The input is given from Standard Input in the following format:  X       Output Print the eventual length of X .        Sample Input 1 TSTTSS      Sample Output 1 4  In the 1 -st operation, the 2 -nd and 3 -rd characters of TSTTSS are removed. X becomes TTSS , and since it does not contain ST anymore, nothing is done in the remaining 10^{10000}-1 operations.
Thus, the answer is 4 .       Sample Input 2 SSTTST      Sample Output 2 0  X will eventually become an empty string: SSTTST ⇒ STST ⇒ ST ⇒ ``.       Sample Input 3 TSSTTTSS      Sample Output 3 4  X will become: TSSTTTSS ⇒ TSTTSS ⇒ TTSS .

Solution (Python):
X = input()

stack_s = []
out = []

for x in X:
    if x == "S":
        stack_s.append("S")
    else:
        if len(stack_s) > 0:
            stack_s.pop()
        else:
            out.append("T")

while len(stack_s) > 0:
    out.append(stack_s.pop())

print(len(out))

Solution (Python):
t=input()
n=len(t)
ans=0
s=0
for i in range(n):
    if t[i]=="S":
        s+=1
    if s>0 and t[i]=="T":
        ans+=1
        s-=1
print(n-2*ans)

Solution (Python):
X = input()
l = []
for i in range(len(X)):
    if X[i] == "S":
        l.append("S")
    elif X[i] == "T":
        if len(l) > 0 and l[-1] == "S":
            l.pop(-1)
        
        else:
            l.append("T")
ans = len(l)
print(ans)

Solution (Python):
X = open(0).read().split()[0]
ans = 0
s_count = 0
for x in X:
    if x == 'T':
        if s_count == 0:
            ans += 1
        else:
            s_count -= 1
    else:
        s_count += 1
print(ans+s_count)

Solution (Python):
import bisect, collections, copy, heapq, itertools, math, string, sys
input = lambda: sys.stdin.readline().rstrip() 
sys.setrecursionlimit(10**7)
INF = float('inf')
def I(): return int(input())
def F(): return float(input())
def SS(): return input()
def LI(): return [int(x) for x in input().split()]
def LI_(): return [int(x)-1 for x in input().split()]
def LF(): return [float(x) for x in input().split()]
def LSS(): return input().split()

def resolve():
    X = SS()

    stk = []

    len_X = len(X)
    ans = len_X
    for i in range(len_X):
        if X[i] == 'S':
            stk.append('S')
        else:
            if stk and stk[-1] == 'S':
                stk.pop()
                ans -= 2

    print(ans)

if __name__ == '__main__':
    resolve()

Solution (Python):
import sys
input = sys.stdin.readline

S = input().rstrip()
s_cnt =0
t_cnt =0

for s in S:
    if s == 'S':
        s_cnt += 1
    else:
        if s_cnt >0:
            s_cnt -= 1
        else:
            t_cnt += 1
            
print(t_cnt + s_cnt)

Solution (Python):
S = input()
s_cnt =0
t_cnt =0

for s in S:
    if s == 'S':
        s_cnt += 1
    else:
        if s_cnt >0:
            s_cnt -= 1
        else:
            t_cnt += 1
            
print(t_cnt + s_cnt)

Solution (Python):
S = input()
s_cnt =0
t_cnt =0

for s in S:
    if s == 'S':
        s_cnt += 1
    if s == 'T':
        t_cnt += 1
        if s_cnt >0:
            t_cnt -= 1
            s_cnt -= 1
print(t_cnt + s_cnt)

Solution (Python):
s = input()
s_cnt =0
t_cnt =0
cnt = 0

for i in range(len(s)):
    if s[i] == 'S':
        s_cnt += 1
    if s[i] == 'T':
        t_cnt += 1
        if s_cnt >0:
            t_cnt -= 1
            s_cnt -= 1
print(t_cnt + s_cnt)

Solution (Python):
X = input()

cache = 0
ans = len(X)

for c in X:
    if c == 'S':
        cache += 1
    else:
        if cache > 0:
            cache -= 1
            ans -= 2

print(ans)

Solution (Python):
def getN():
    return int(input())
def getNM():
    return map(int, input().split())
def getList():
    return list(map(int, input().split()))
def getArray(intn):
    return [int(input()) for i in range(intn)]
def input():
    return sys.stdin.readline().rstrip()
def rand_N(ran1, ran2):
    return random.randint(ran1, ran2)
def rand_List(ran1, ran2, rantime):
    return [random.randint(ran1, ran2) for i in range(rantime)]
def rand_ints_nodup(ran1, ran2, rantime):
  ns = []
  while len(ns) < rantime:
    n = random.randint(ran1, ran2)
    if not n in ns:
      ns.append(n)
  return sorted(ns)

def rand_query(ran1, ran2, rantime):
  r_query = []
  while len(r_query) < rantime:
    n_q = rand_ints_nodup(ran1, ran2, 2)
    if not n_q in r_query:
      r_query.append(n_q)
  return sorted(r_query)

from collections import defaultdict, deque, Counter
from sys import exit
from decimal import *
import heapq
from math import sqrt
from fractions import gcd
import random
import string
import copy
from itertools import combinations, permutations, product
from operator import mul, itemgetter
from functools import reduce
from bisect import bisect_left, bisect_right

import sys
sys.setrecursionlimit(1000000000)
mod = 10 ** 9 + 7





S = input()
N = len(S)

s_cnt = 0
ans = 0
for i in range(N):
    if S[i] == 'S':
        s_cnt += 1
    else:
        if s_cnt == 0:
            ans += 1
        else:
            s_cnt -= 1
print(s_cnt + ans)

Solution (Python):
X = input()
s_cnt = 0
ans = 0
for s in X:
    if s=='S':
        s_cnt += 1
    else:
        if s_cnt > 0:
            ans += 1
            s_cnt -= 1

print(len(X) - 2*ans)

Solution (Python):
def main():
    x = input()
    s, t = 0, 0
    for i in x:
        if i == "S":
            s += 1
        else:
            if s:
                s -= 1
            else:
                t += 1
    print(s + t)

if __name__ == "__main__":
    main()

Solution (Python):
s = input()
n = len(s)
ans = []
for i in range(n):
    if s[i] == "S":
        ans.append(s[i])
    else:
        if ans == [] or ans[-1] != "S":
            ans.append(s[i])
        else:
            ans.pop()
print(len(ans))

Solution (Python):
x = input()
n = len(x)

stack=[]
ans = 1
for i in range(n):
    if(len(stack) > 0 and x[i] == 'T' and stack[-1] == 'S'):
        ans += 1
        stack.pop()
    else:
        stack.append(x[i])
    
print(len(stack))

Solution (Python):
x=input()
n=len(x)
s=0
for i in x:
  if s and i=='T':s-=1
  if i=='S':s+=1
print(2*s)

Solution (Python):
import sys

readline = sys.stdin.readline
MOD = 10 ** 9 + 7
INF = float('INF')
sys.setrecursionlimit(10 ** 5)


def main():
    s = input()
    ans = len(s)
    cnt = 0

    for char in s:
        if char == "S":
            cnt += 1
        else:
            if cnt > 0:
                cnt -= 1
                ans -= 2

    print(ans)


if __name__ == '__main__':
    main()

Solution (Python):
def main():
    X = input()
    S_COUNT = 0
    delete = 0
    for c in X:
        if c == "S":
            S_COUNT += 1
        else:
            if S_COUNT:
                delete += 2
                S_COUNT -= 1
                
    print(len(X)-delete)
if __name__ == "__main__":
    main()

Solution (Python):
from collections import deque
X = input()
que = deque()
for x in X:
    if x=='S':
        que.append('S')
    elif x=='T' and (not que or que[-1]=='T'):
        que.append('T')
    elif x=='T' and que[-1]=='S':
        _ = que.pop()
print(len(que))

Solution (Python):
from math import ceil,floor,comb,factorial,gcd,pow,sqrt,log2,cos,sin,tan,acos,asin,atan,degrees,radians,pi,inf
from itertools import accumulate,permutations,combinations,product,combinations_with_replacement
from collections import deque,defaultdict,Counter
from bisect import bisect_left,bisect_right
from operator import itemgetter
from heapq import heapify,heappop,heappush
from copy import deepcopy
from time import time
import string
import sys
sys.setrecursionlimit(10 ** 7)
def input() : return sys.stdin.readline().strip()
def INT()   : return int(input())
def MAP()   : return map(int,input().split())
def LIST()  : return list(MAP())

x = input()
s = 0
ans = len(x)
for i in range(len(x)):
    if x[i] == 'S':
        s += 1
    else:
        if s > 0 :
            s -= 1
            ans -= 2

print(ans)

Solution (Python):
string = input()
stack = []
for c in string:
    if len(stack) == 0:
        stack.append(c)
        continue
    if stack[-1] + c == 'ST':
        stack.pop()
    else:
        stack.append(c)

print(len(stack))

Solution (Python):
X = input()
s_cnt = 0
ans = 0
for s in X:
    if s=='S':
        s_cnt += 1
    else:
        if s_cnt > 0:
            ans += 1
            s_cnt -= 1

print(len(X) - 2*ans)

Solution (Python):
import sys
import itertools

read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline

in_n = lambda: int(readline())
in_nn = lambda: map(int, readline().split())
in_nl = lambda: list(map(int, readline().split()))
in_na = lambda: map(int, read().split())
in_s = lambda: readline().rstrip().decode('utf-8')


def main():
    S = list(in_s())[::-1]
    N = len(S)

    gr = itertools.groupby(S)

    count = 0
    tnum = 0
    for k, v in gr:
        num = sum(1 for _ in v)
        if k == 'S':
            count += min(tnum, num)
            tnum -= min(tnum, num)
        else:
            tnum += num

    

    ans = N - count * 2
    print(ans)


if __name__ == '__main__':
    main()

Solution (Python):
def main():
  S = str(input())
  ans = 0
  num_t = 0
  for i in range(len(S)-1, -1, -1):
    if S[i] == 'T':
      flag = True
      num_t += 1
    if S[i] == 'S' and num_t > 0 :
      num_t -= 1
      ans += 2
  print(len(S)-ans)
  
if __name__ == "__main__":
  main()

Solution (Python):
x = input()

s, t = 0, 0
for i in x:
    if i == 'S':
        s += 1
    elif i == 'T':
        if s > 0:
            s -= 1
        else:
            t += 1
print(s + t)

Solution (Python):
s=t=0
for i in input():
    if i=="S":s+=1
    elif s>0:s-=1
    else:t+=1
print(s+t)

Solution (Python):
s=t=0
for i in input():
    if i=="S":
        s+=1
    elif s>0:s-=1
    else:t+=1
print(s+t)

Solution (Python):
s=t=0
for i in input():
  if i=="S":s+=1
  else:
    if s:s-=1
    else:t+=1
print(s+t)

Solution (Python):
a=[]
for i in input():
    if i=="S":
        a+=i
    
    if a:
        if i=="T" and a[-1]=="T":
            a+=i
        if i=="T" and a[-1]=="S":
            a.pop(-1)
    elif i=="T" and len(a)==0:
        a+=i    
print(len(a))

Solution (Python):
x = list(input())
cnt = 0
a = 0
for i in x:
  if i == 'S':
    cnt += 1
  elif i == 'T':
    if cnt > 0:
      cnt -= 1
    else:
      a += 1
print(a+cnt)

Solution (Python):
import sys, re
from collections import deque, defaultdict, Counter
from math import ceil, sqrt, hypot, factorial, pi, sin, cos, tan, asin, acos, atan, radians, degrees, log2, gcd
from itertools import accumulate, permutations, combinations, combinations_with_replacement, product, groupby
from operator import itemgetter, mul
from copy import deepcopy
from string import ascii_lowercase, ascii_uppercase, digits
from bisect import bisect, bisect_left, insort, insort_left
from heapq import heappush, heappop
from functools import reduce
def input(): return sys.stdin.readline().strip()
def INT(): return int(input())
def MAP(): return map(int, input().split())
def LIST(): return list(map(int, input().split()))
def ZIP(n): return zip(*(MAP() for _ in range(n)))
sys.setrecursionlimit(10 ** 9)
INF = float('inf')
mod = 10 ** 9 + 7 

from decimal import *



X = input()

cnt = 0
s = 0

for i in range(len(X)):
	if X[i] == "S":
		s += 1
	else:
		if 0 < s:
			cnt += 1
			s -= 1

print(len(X)-2*cnt)

Solution (Python):

x = input()
while 'ST' in x:
    x = x.replace('ST', '')
    
    n = len(x) // 2
    if ('T' not in x[:n]) and ('S' not in x[n:]):
        x = ''
        break
print(len(x))

Solution (Python):
x = input()
while 'ST' in x:
    x = x.replace('ST', '')
    n = len(x) // 2
    if ('T' not in x[:n]) and ('S' not in x[n:]):
        x = ''
        break
print(len(x))

Solution (Python):
x=input()
s,t=0,0

for m in x:
  if m=="S":
    s+=1
  else:
    if s>0:
      s-=1
    else:
      t+=1
print(s+t)

Solution (Python):
x = input()

ans = 0
s_cnt = 0

for i in range(len(x)):
    if s_cnt == 0:
        if x[i] == 'T':
            ans += 1
        else:
            s_cnt += 1
    else:
        if x[i] == 'T':
            s_cnt -= 1
        else:
            s_cnt += 1

if s_cnt > 0:
    ans += s_cnt

print(ans)

Solution (Python):
import sys
input = lambda : sys.stdin.readline().rstrip()
sys.setrecursionlimit(max(1000, 10**9))
write = lambda x: sys.stdout.write(x+"\n")


x = input()
s = []
for c in x:
    if c=="T" and s and s[-1]=="S":
        s.pop()
    else:
        s.append(c)
ans = len(s)
print(ans)

Solution (Python):
x = input()

s, t = 0, 0
ols = 0
cnt = 0
for i in x:
  if i == "S":
    s += 1
  else:
    if s > 0:
     cnt += 1
     s -= 1
     s = max(s,0)
print (len(x)-cnt*2)

Solution (Python):
s = input()

now_try = 0
idx = 0
while idx < len(s) - 1:

    if s[idx] == 'T':
        idx += 1
        continue

    if s[idx] == 'S':
        if s[idx + 1] == 'T':
            s = s[:idx] + s[idx + 2:]
            now_try += 1
            idx = idx - 1 if idx - 1 >= 0 else 0
        else:
            idx += 1

print(len(s))

Solution (Python):
X = input()

ans = len(X)
s = 0
for x in X:
    if x == "S":
        s += 1
    else:
        if s:
            ans -= 2
            s -= 1
print(ans)

Solution (Python):
def runlength(S):
    A = []
    tmp = S[0]
    cnt = 0
    for i in range(len(S)):
        if S[i] == tmp:
            cnt += 1
        else:
            A.append(cnt)
            tmp = S[i]
            cnt = 1
    else:
        A.append(cnt)
    return A

def main():
    X = input()
    Y = runlength(X)
    if X[0] == 'T':
        Y = [0] + Y
    
    if X[-1] == 'S':
        Y += [0]

    ans = len(X)
    amari = 0
    for i in range(0,len(Y),2):
        ans -= 2 * min(amari + Y[i], Y[i+1])
        amari = max(0, amari + Y[i] - Y[i+1])

    print(ans)


if __name__ == "__main__":
    main()

Solution (Python):
X = str(input())

Tn = 0
Sn = 0
Nagasa = len(X)

for i in range (0, Nagasa):
	if X[i] == 'T':
		if Sn == 0:
			Tn+=1
		else:
			Sn-=1
	else:
		Sn+=1

print(2*Tn)

Solution (Python):
x=input()
n=len(x)

t=0
cnt=0
for i in range(n-1,-1,-1):
    if x[i]=='T':
        t+=1
    elif t>0 and x[i]=='S':
        cnt+=1
        t-=1

print(n-2*cnt)

Solution (Python):
x = input()
cnt = 0
for x_ in x:
    if x_ == 'T' and cnt:
        cnt -= 1
    elif x_ == 'S':
        cnt += 1
print(2 * cnt)

Solution (Python):
X = input()

cntS = 0
res = 0
for x in X:
    if x == "S":
        cntS += 1
    elif cntS > 0:
        cntS -= 1
    else:
        res += 1

print(res + cntS)

Solution (Python):
X = input()
 
val = len(X)
sum = 0
for i in X:
    if i == "S":
        sum += 1
    else:
        if sum > 0:
            val -= 2
            sum -= 1
 
print(val)

Solution (Python):
X = input()
lis = []
if X[0] == 'S':
    lis.append(0)
cnt = 1
for i in range(1,len(X)):
    if X[i] != X[i-1]:
        lis.append(cnt)
        cnt = 0
    cnt += 1
lis.append(cnt)
if X[-1] == 'T':
    lis.append(0)
else:
    lis += [0,0]

ans = lis[0]
for i in range(1,len(lis)-2,2):
    if lis[i] < lis[i+1]:
        ans += lis[i+1]-lis[i]
        lis[i+1] -= lis[i]
    else:
        lis[i+2] += lis[i] - lis[i+1]
        lis[i+1] = 0
ans += (lis[-1] + lis[-2])

print(ans)

Solution (Python):
X = input()
 
val = len(X)
sum = 0
for i in X:
    if i == "S":
        sum += 1
    else:
        if sum > 0:
            val -= 2
            sum -= 1
 
print(val)

Solution (Python):


s = input()
x = 0
y = 0
for i in s:
    if i == 'S':
        y -= 1
    else:
        y += 1
    
    x = max(x, y)
    
print(x*2)

Solution (Python):
def resolve():
    from collections import deque
    x = input()
    final = deque([])
    final.append(x[0])
    for i in range(1, len(x)):
        if x[i] == "S":
            final.append("S")
        else:
            if not final:
                final.append("T")
            else:
                last = final.pop()
                if last == "S":
                    continue
                else:
                    final.append("T")
                    final.append("T")
    print(len(final))
resolve()

Solution (Python):
string = input()

length = len(string)
sindex = 0
for i in range(0, length):
  if string[i] == "S": 
    sindex = i
    break
    
s_count = 0

for i in range(sindex, len(string)):
  if string[i] == "S": s_count += 1
  if string[i] == "T" and s_count > 0:
    s_count -= 1
    length -= 2
    
print(length)

Solution (Python):
x = input()

n = len(x)
a = []
for i in range(n):
  if x[i]=="S":
    a.append(x[i])
  else:
    if len(a)!=0 and a[-1]=='S' :
      a.pop()
    else:
      a.append(x[i])
print(len(a))

Solution (Python):
x = input()
scount, tcount, c = 0, 0, 0
for i in range(len(x)):
  if x[c]=="S":
    scount+=1
  else:
    if scount>0:
      scount-=1
    else:
      tcount+=1
  c+=1
print(tcount*2)

Solution (Python):

from collections import deque, Counter
from heapq import heappop, heappush
from bisect import bisect_right

def main():
    X = input()
    ans = 0
    now = 0
    for x in X:
        if x == 'S':
            now -= 1
        else:
            now += 1
        ans = max(ans,now)
    print(ans*2)

if __name__ == "__main__":
    main()

Solution (Python):
def main():
    X = input()
    cs, ct = 0, 0
    for x in X:
        if x == 'T':
            if cs == 0:
                ct += 1
            else:
                cs -= 1
        else:
            cs += 1
    print(ct * 2)
if __name__ == '__main__':
    main()

Solution (Python):
X = input()
cnt = 0
for x in X:
    if x == 'T' and cnt:
        cnt -= 1
    elif x == 'S':
        cnt += 1
print(2*cnt)

Solution (Python):
s = input()
ans = 0
cnt = 0
for i in s:
    if i == "S":
        cnt += 1
    else:
        if cnt:
            ans += 1
            cnt -= 1
print(len(s) - (2*ans))

Solution (Python):



from fractions import gcd
from itertools import combinations,permutations,accumulate 

from collections import deque,defaultdict,Counter











import sys
sys.setrecursionlimit(10000000)
mod = 10**9 + 7

def readInts():
  return list(map(int,input().split()))
def I():
  return int(input())
X = input()
sc = 0
cnt = 0
ln = len(X)
for i in range(ln):
    if X[i] == 'S':
        sc += 1
    if X[i] == 'T':
        if sc >= 1:
            sc -= 1
            cnt += 1
print(ln - cnt * 2)

Solution (Python):
X = list(str(input()))
n = len(X)

s = []
for x in X:
    if x == 'S':
        s.append(x)
    if x == 'T':
        if s:
            if s[-1] == 'S':
                s.pop()
            else:
                s.append(x)
        else:
            s.append(x)
print(len(s))

Solution (Python):
X = list(str(input()))
n = len(X)

s = []
for x in X:
    if x == 'S':
        s.append(x)
    if x == 'T':
        if s:
            if s[-1] == 'S':
                s.pop()
            else:
                s.append(x)
        else:
            s.append(x)
print(len(s))

Solution (Python):
X = input()
N = len(X)
c = 0
s, t = 0, 0
for k in range(N):
    if X[k] == "S":
        s += 1
    else:
        t += 1
        if s > 0 and t > 0:
            s -= 1
            t -= 1
            c += 2
print(N-c)

Solution (Python):
X = input()
stack = []
for c in X:
    if not stack:
        stack.append(c)
        continue
    if stack[-1] == "S" and c == "T":
        stack.pop()
    else:
        stack.append(c)
print(len(stack))

Solution (Python):
def solve():
    ans = 0
    X = input()
    num = 0
    for x in X:
        if x=='S':
            num += 1
        else:
            if num>0:
                num -= 1
    ans = num*2
    return ans
print(solve())

Solution (Python):
x = input()

cnt = 0
numt = 0
x = x[::-1]
for i in range(len(x)):
    if x[i] == 'T':
        numt += 1
    else:
        if numt > 0:
            cnt += 1
            numt -= 1
print(len(x)-2*cnt)

Solution (Python):
S=input()
score=0
maxscore=0
for i in range(len(S)):
  if S[i]=='T':
    score+=1
    maxscore=max(maxscore,score)
  else:
    score-=1
print(2*maxscore)

Solution (Python):
X = input()

ans = len(X)
tmp_s = 0
for i in X:
    if i == "S":
        tmp_s += 1
    else:
        if tmp_s > 0:
            ans -= 2
            tmp_s -= 1

print(ans)

Solution (Python):
x=input()
s=t=0
for i in x:
  if i=="S":s+=1
  else:
    if s:
      s-=1
    else:
      t+=1
print(s+t)

Solution (Python):
S = input()
k = 0
l = len(S)
for i in S:
  if i == 'S':
    k += 1
  else:
    if k > 0:
      k -= 1
      l -= 2
print(l)

Solution (Python):
X = input()

s = 0
cnt = 0
for i in range(len(X)):
    if X[i] == "S":
        s += 1
    elif s > 0:
        s -= 1
        cnt += 1

print(len(X)-2*cnt)

Solution (Python):

X=input()

cnt=0
numS=0
for i in range(len(X)):
    if X[i]=="S":
        numS+=1
    elif numS>0:
        cnt+=1
        numS-=1

print(len(X)-2*cnt)

Solution (Python):
s = input()

S = 0
T = 0

for c in s:
  if c == 'S':
    S += 1
  else:
    if S > 0:
      S -= 1
    else:
      T += 1
      
print(S+T)

Solution (Python):
X=list(input())
ans=0
cnt=0
for i in range(len(X)):
  if cnt==0:
    if X[i]=="T":
      ans+=1
    else:
      cnt+=1
  else:
    if X[i]=="T":
      cnt-=1
    else:
      cnt+=1
    
print(ans+cnt)

Solution (Python):
S = input()

T_count = 0
S_count = 0
ans = 0
for i in range(len(S)):
    if S[i] == "S":
        S_count += 1
    else:
        if S_count > T_count:
            T_count += 1
        else:
            ans += 2
            
print(ans)

Solution (Python):



def main():
    S = input()
    cnt = 0
    ret = len(S)
    for a in S:
        if a == 'S':
            cnt += 1
        else:
            if cnt>0:
                cnt-=1
                ret-=2
    print(ret)

if __name__ == '__main__':
    main()

Solution (Python):
X = input()
stack = []
for c in X:
    if not stack:
        stack.append(c)
    elif stack[-1] == "S" and c == "T":
        stack.pop()
    else:
        stack.append(c)
print(len(stack))

Solution (Python):
import sys

read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines

X = read().rstrip().decode()

s, t = 0, 0
for x in X:
    if x == 'S':
        s += 1
    else:
        if s == 0:
            t += 1
        else:
            s -= 1

print(s+t)

Solution (Python):
S = input()

ans = len(S)
s = 0
for i in range(ans):
    if S[i] == "S":
        s += 1
    else:
        if s > 0:
            s -= 1
            ans -= 2

print(ans)

Solution (Python):
X = list(input())

cnt = 0
s = 0
for i in range(len(X)):
    if X[i] == "S":
        s += 1
    else:
        if s:
            cnt += 2
            s -= 1
print(len(X)-cnt)

Solution (Python):
import sys
X = sys.stdin.readline().rstrip()
S = 0
T = 0
ans = 0
for x in X:
    if x == "S":
        S += 1
    else:
        if not S:
            ans += 1
        else:
            S -= 1
ans += S
print(ans)

Solution (Python):
def main():
    X = input()
    delcnt = 0
    delans = 0
    for i in range(len(X)):
        if X[i]=='S':
            delcnt += 1
        if X[i]=='T' and delcnt>0:
            delans +=2
            delcnt -=1
    print(len(X)-delans)



if __name__ == '__main__':
    main()

Solution (Python):
x = input()
res = [x[0]]
for i in x[1:]:
  if i == 'S':
    res += [i]
  elif not res:
    res += [i]
  else:
    if res[-1] == 'S':
      res.pop()
    else:
      res += [i]
print(len(res))

Solution (Python):

import sys
from collections import deque


def solve(X: str):
    stack = deque(X[0])
    for i in range(1, len(X)):
        if not stack:
            stack.append(X[i])
            continue
        if stack[-1] == "T":
            stack.append(X[i])
            continue
        if X[i] == "T":
            stack.pop()
            continue
        stack.append(X[i])

    print(len(stack))



def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    X = next(tokens)  
    solve(X)

if __name__ == '__main__':
    main()

Solution (Python):
X=input()
ans=len(X)
count_s=0
for i in X:
    if i=='S':
        count_s+=1
    if i=='T' and count_s>=1:
        count_s-=1
        ans-=2

print(ans)

Solution (Python):
x = list(input())
n = len(x)
ct = 0
cs = 0
c = 0
for X in x:
    if X == "S":
        cs += 1
    else:
        ct += 1
        if cs >= 1:
            cs -= 1
            c += 1
print(n-2*c)

Solution (Python):
def main(X):
    cntS = 0; cntT = 0
    for x in X:
        if x == 'T' and cntS == 0:
            cntT += 1
        elif x == 'S':
            cntS += 1
        elif x == 'T' and cntS > 0:
            cntS -= 1
        else:
            pass
    return cntS + cntT
    
if __name__ == "__main__":
    X = list(input())
    ans = main(X)
    print(ans)

Solution (Python):
seq=input()

s=0
t=0
c=0

for si in seq:
    if si=="S":
        s+=1
    else:
        if s==0:
            c+=1
        else:
            s-=1
c+=s

print(c)

Solution (Python):






import sys
input = sys.stdin.readline

import math

import bisect
from collections import defaultdict
from collections import deque
from collections import Counter
from functools import lru_cache






MOD = 10**9+7
INF = float('inf')






def I(): return int(input().strip())
def S(): return input().strip()
def IL(): return list(map(int,input().split()))
def SL(): return list(map(str,input().split()))
def ILs(n): return list(int(input()) for _ in range(n))
def SLs(n): return list(input().strip() for _ in range(n))
def ILL(n): return [list(map(int, input().split())) for _ in range(n)]
def SLL(n): return [list(map(str, input().split())) for _ in range(n)]


def P(arg): print(arg); return
def Y(): print("Yes"); return
def N(): print("No"); return
def E(): exit()
def PE(arg): print(arg); exit()
def YE(): print("Yes"); exit()
def NE(): print("No"); exit()


def DD(arg): return defaultdict(arg)



def inv(n): return pow(n, MOD-2, MOD)


kaijo_memo = []
def kaijo(n):
  if(len(kaijo_memo) > n):
    return kaijo_memo[n]
  if(len(kaijo_memo) == 0):
    kaijo_memo.append(1)
  while(len(kaijo_memo) <= n):
    kaijo_memo.append(kaijo_memo[-1] * len(kaijo_memo) % MOD)
  return kaijo_memo[n]

gyaku_kaijo_memo = []
def gyaku_kaijo(n):
  if(len(gyaku_kaijo_memo) > n):
    return gyaku_kaijo_memo[n]
  if(len(gyaku_kaijo_memo) == 0):
    gyaku_kaijo_memo.append(1)
  while(len(gyaku_kaijo_memo) <= n):
    gyaku_kaijo_memo.append(gyaku_kaijo_memo[-1] * pow(len(gyaku_kaijo_memo),MOD-2,MOD) % MOD)
  return gyaku_kaijo_memo[n]

def nCr(n,r):
  if(n == r):
    return 1
  if(n < r or r < 0):
    return 0
  ret = 1
  ret = ret * kaijo(n) % MOD
  ret = ret * gyaku_kaijo(r) % MOD
  ret = ret * gyaku_kaijo(n-r) % MOD
  return ret


def factorization(n):
  arr = []
  temp = n
  for i in range(2, int(-(-n**0.5//1))+1):
    if temp%i==0:
      cnt=0
      while temp%i==0: 
        cnt+=1 
        temp //= i
      arr.append([i, cnt])
  if temp!=1:
    arr.append([temp, 1])
  if arr==[]:
    arr.append([n, 1])
  return arr


def make_divisors(n):
  divisors = []
  for i in range(1, int(n**0.5)+1):
    if n % i == 0:
      divisors.append(i)
      if i != n // i: 
        divisors.append(n//i)
  return divisors


def make_primes(N):
  max = int(math.sqrt(N))
  seachList = [i for i in range(2,N+1)]
  primeNum = []
  while seachList[0] <= max:
    primeNum.append(seachList[0])
    tmp = seachList[0]
    seachList = [i for i in seachList if i % tmp != 0]
  primeNum.extend(seachList)
  return primeNum


def gcd(a, b):
    while b:
        a, b = b, a % b
    return a


def lcm(a, b):
    return a * b // gcd (a, b)


def count_bit(n):
  count = 0
  while n:
    n &= n -1
    count += 1
  return count


def base_10_to_n(X, n):
  if X//n:
    return base_10_to_n(X//n, n)+[X%n]
  return [X%n]

def base_n_to_10(X, n):
  return sum(int(str(X)[-i-1])*n**i for i in range(len(str(X))))


def int_log(n, a):
  count = 0
  while n>=a:
    n //= a
    count += 1
  return count





S = S()
SUM = 0
MAX = 0
for s in S:
  if s == "T":
    SUM += 1
    MAX = max(MAX,SUM)
  else:
    SUM -= 1
print(MAX*2)

Solution (Python):
x = str(input())
cnt = 0
tmp = 0
for i in x:
    if i == 'T':
        if tmp > 0:
            tmp -= 1
        else:
            cnt += 1
    else:
        tmp += 1
else:
    print(cnt + tmp)

Solution (Python):
x = list(map(str, input().rstrip()))

stock = 0
rest = 0
for i in x:
    if i == "S":
        stock += 1
    elif i == "T" and stock >= 1:
        stock -= 1
    else:
        rest += 1

print(stock + rest)

Solution (Python):
x = input()
ls = []
ans = len(x)
for i in range(len(x)):
    if x[i] == "S":
        ls.append("S")
    else:
        if len(ls):
            ls.pop()
            ans -= 2
print(ans)

Solution (Python):
x = input()

pair_cnt = 0
s_cnt = 0
for i in x:
    if i == "S":
        s_cnt += 1
    elif i == "T" and s_cnt:
        pair_cnt += 1
        s_cnt -= 1

print(len(x) - pair_cnt * 2)

Solution (Python):
X = list(input())

st = []
for x in X:
    if x == 'S':
        st.append(x)
    else:
        if len(st) > 0 and st[-1] == 'S':
            st.pop()
        else:
            st.append(x)
print(len(st))

Solution (Python):
x=input()
s,a=0,0
for i in x:
 if i=="S":
  s+=1
 elif s==0:
  a+=1
 else:
  s-=1
print(a+s)

Solution (Python):
import sys


import math
import collections

import bisect
import itertools
import fractions

import copy
import heapq
import decimal

import queue
import numpy as np

sys.setrecursionlimit(10000001)
INF = 10 ** 16
MOD = 10 ** 9 + 7

ni = lambda: int(sys.stdin.readline())
ns = lambda: map(int, sys.stdin.readline().split())
na = lambda: list(map(int, sys.stdin.readline().split()))





def main():
    x = list(input())
    s_cnt = 0

    ans = len(x)
    for xi in x:
        if xi == "S":
            s_cnt += 1
        else:
            if s_cnt != 0:
                s_cnt -= 1
                ans -= 2

    print(ans)


if __name__ == '__main__':
    main()

Solution (Python):
s = input()
cur = 0
deletedpairs = 0
for i in range(len(s)):
    
    if s[i] == "S":
        cur += 1
    if s[i] == "T":
        if cur > 0:
            deletedpairs += 1
            cur -= 1
        else:
            pass


print(len(s) - deletedpairs*2)

Solution (Python):
S = input()

num_s = 0

ans = 0
for c in S:
    if c == "S":
        num_s += 1
    else:
        if num_s > 0:
            num_s -= 1
        else:
            ans += 1

ans += num_s

print(ans)

Solution (Python):
x = input()
s_cnt = 0
t_cnt = 0
ans = 0
tmp = 0
for s in x:
    if s == "T":
        if tmp == 0:
            ans += 2
        else:
            tmp -= 1
    else:
        tmp += 1
print(ans)

Solution (Python):
def main():
    from sys import setrecursionlimit, stdin
    from os import environ
    from collections import defaultdict, deque, Counter
    from math import ceil, floor
    from itertools import accumulate, combinations, combinations_with_replacement
    setrecursionlimit(10**6)
    dbg = (lambda *something: print(*something)) if 'TERM_PROGRAM' in environ else lambda *x: 0
    input = lambda: stdin.readline().rstrip()
    LMIIS = lambda: list(map(int,input().split()))
    II = lambda: int(input())
    P = 10**9+7
    INF = 10**9+10

    S = input()
    num_s = 0
    ans = len(S)
    for c in S:
        if c == 'S':
            num_s += 1
        else:
            if num_s > 0:
                num_s -= 1
                ans -= 2
    print(ans)

    
main()