Harryxun/stf_run huggingface dataset:
import sys
data = sys.stdin.readlines()
n = int(data[0])
cost = 0
points = []
for i in range(n):
    xy = data[i+1].split()
    x = int(xy[0])
    y = int(xy[1])
    points.append((x,y))

while len(points) != 0:
    p = points[-1][0] - points[-2][0]
    q = points[-1][1] - points[-2][1]
    xn = points[-1][0] - p
    yn = points[-1][1] - q
    cost +=1
    points.pop()
    #print(p, " ", q)
    while len(points) != 0:
        if points[-1][0] == xn and points[-1][1] == yn:
            xn = points[-1][0] - p
            yn = points[-1][1] - q
            points.pop()
        else:
            break

print(cost)

### FIXED CODE ###

n = int(input())
if n ==1:
    print( 1)
    exit()
cost = 0
points = []
for i in range(n):
    points.append(list(map(int, input().split())))

points.sort()
dictpq = {}
for i in range(n):
    for j in range(i+1,n):
        p = points[i][0] - points[j][0]
        q = points[i][1] - points[j][1]
        if (p,q) in dictpq:
            dictpq[(p,q)] +=1
        else:
            dictpq[(p,q)] =1
print(n-max(dictpq.values()))
n = int(input())
data = list(map(int, input.split()))
datad = data.sort(reverse = True)
a = sum(datad[::2])
b = sum(datad[1::2])
print(a - b)

### FIXED CODE ###

n = int(input())
a = list(map(int, input().split()))
b = a.sort(reverse = True)
print(sum(a[::2])-sum(a[1::2]))
a = 1
while True:
	if b != 0:
		b = int(raw_input())
		print('Case ' + str(a) + ': ' + str(b))
		a += 1
		continue
	else:
		break

### FIXED CODE ###

a = int(1)
b = int(1)
while True:
	b = int(raw_input())
	if b != 0:
		print('Case ' + str(a) + ': ' + str(b))
		a += 1
		continue
	else:
		break
N, i = map(int, input().split())
print(N-i+1))

### FIXED CODE ###

N, i = map(int, input().split())
print(N-i+1)
K,N=map(int,input().split())
A=[list(map(int,input().split()))]
del A[index(min(A))]
for a in A:
  a-=min(A)
print(max(A)-min(A))

### FIXED CODE ###

K,N=map(int,input().split())
A=list(map(int,input().split()))
B=sorted(A)
C=[]
for i in range(N-1):
    C.append(B[i+1]-B[i])
C.append(B[0]+K-B[N-1])
print(K-max(C))
n, q = map(int,input().split())
s = list(input())
t = [0]*(n+1)
j = 0
for j in range(n):
    if s[j]=="A" and s[j+1]=="C":
        t[j+1]=t[j]+1
    else:
        t[j+1]=t[j]
i = 0
for i in range(q):
    a,b = map(int,input().split())
    print((t[b-1])-(t[a-1]))

### FIXED CODE ###

n, q = map(int,input().split())
s = list(input())
t = [0]*(n)
j = 0
for j in range(n-1):
    if s[j]=="A" and s[j+1]=="C":
        t[j+1]=t[j]+1
    else:
        t[j+1]=t[j]
i = 0
for i in range(q):
    a,b = map(int,input().split())
    print((t[b-1])-(t[a-1]))
a,b,k=map(int,input().split())
c=0
n=0
if a>b:
    n=a-b
if b>a:
    n=b-a
if a==b:
    n=1
while(True):
    if(a%n==0)&(b%n==0):
        c=c+1
    if c==k:
        break
    n=n-1
print(n)

### FIXED CODE ###

a,b,k=map(int,input().split())
c=0
n=0
if a>b:
    n=a-b
if b>a:
    n=b-a
if a==b:
    n=a
while(True):
    if(a%n==0)&(b%n==0):
        c=c+1
    if c==k:
        break
    n=n-1
print(n)
# -*- coding: utf-8 -*-
n = int(input())
li = [map(int, input().split())]
ans = 'Yes'

if n > 1:
  for i in range(n-1):
    if li[-(i+2)] <= li[-(i+1)]:
      pass
    elif li[-(i+2)] - 1 <= li[-(i+1)]:
      li[-(i+2)] = li[-(i+2)] - 1
    else:
      ans = 'No'
      break

print(ans)

### FIXED CODE ###

# -*- coding: utf-8 -*-
n = int(input())
li = [int(a) for a in input().split()]
ans = 'Yes'

if n > 1:
  for i in range(n-1):
    if li[-(i+2)] <= li[-(i+1)]:
      pass
    elif li[-(i+2)] - 1 <= li[-(i+1)]:
      li[-(i+2)] = li[-(i+2)] - 1
    else:
      ans = 'No'
      break

print(ans)
S = str(input())
s = list(S)
p = 0
for i in range(2,len(s)-1):
        if s[i] == 'C':
            p = p + 1
            del s[i]
if s[0] == 'A':
    del s[0]
    if p == 1:
        q = ''.join(s)
        if q.islower() == True:
            print('AC')
        else:
            print('WA')
    else:
        print('WA')
else:
    print('WA')

### FIXED CODE ###

S = str(input())
s = list(S)
u = s
p = 0
for i in range(2,len(s)-1):
        if s[i] == 'C':
            p = p + 1
for i in range(2,len(s)-p):
    if s[i] == 'C':
        if i != len(s) - 1:
            del s[i]
if s[0] == 'A':
    del s[0]
    if p == 1:
        q = ''.join(s)
        if q.islower() == True:
            print('AC')
        else:
            print('WA')
    else:
        print('WA')
else:
    print('WA')
list=input().split()
if list[1] == "+":print(list[0]+list[2])
else:print(list[0]-list[2])

### FIXED CODE ###

list=input().split()
if list[1] == "+":print(int(list[0])+int(list[2]))
else:print(int(list[0])-int(list[2]))
x=int(input())
if(x>=25):
  print("Yes")
 else:
  print("No")

### FIXED CODE ###

x=int(input())
if(x>=30):
  print('Yes')
else:
  print("No")
n, m = list(map(int, input().split(' ')))
hn = list(map(int, input().split(' ')))
abm = [None] * m

d = defaultdict(list)
for i in range(m):
    v = list(map(int, input().split(' ')))
    d[v[0]].append(v[1])
    d[v[1]].append(v[0])
    

count = 0

for i in range(1, n + 1):
    cand = d.get(i)
    if cand is None:
        count += 1
        continue
    ok = True
    for c in cand:
        if hn[i - 1] <= hn[c - 1]:
            ok = False
            break
    if ok:
        count += 1
print(count)


### FIXED CODE ###

from collections import defaultdict

n, m = list(map(int, input().split(' ')))
hn = list(map(int, input().split(' ')))
abm = [None] * m

d = defaultdict(list)
for i in range(m):
    v = list(map(int, input().split(' ')))
    d[v[0]].append(v[1])
    d[v[1]].append(v[0])
    

count = 0

for i in range(1, n + 1):
    cand = d.get(i)
    if cand is None:
        count += 1
        continue
    ok = True
    for c in cand:
        if hn[i - 1] <= hn[c - 1]:
            ok = False
            break
    if ok:
        count += 1
print(count)
import sys
n,m = map(int, input().split())

p = [0]*n
q = [False]*n
for i in range(m):
  s,c = map(int, input().split())
  if s == 1 and c == 0 and n != 1:
    #continue
  if s > n:
    print(-1)
    sys.exit()
    
  if q[s-1] == False:
    p[s-1] = c
    q[s-1] = True
  elif p[s-1] > c:
    p[s-1] = c

t = ''
for i in p:
  t += str(i)
  
t = int(t)
if len(str(t)) == n:
  print(t)
else:
  print(-1)

### FIXED CODE ###

n,m = map(int, input().split())

t = [-1]*n
for _ in range(m):
  s,c = map(int, input().split())
  s -= 1
  if t[s] != -1 and t[s] != c:
    print(-1)
    exit()
  t[s] = c
  
if n != 1:
  if t[0] == 0:
    print(-1)
    exit()
    
  if t[0] == -1:
    t[0] = 1
    
  for i in range(1, n):
    if t[i] == -1:
      t[i] = 0
else:
  if t[0] == -1:
    t[0] = 0
    
print(''.join(map(str, t)))
n,z,w=[int(i) for i in input().split(' ')]
a=[int(i) for i in input().split(' ')]

l0=abs(a[-1]-a[-2])
l1=abs(a[-1]-w)

if l1>l0:
  print(l1)
else:
  print(l0)

### FIXED CODE ###

n,z,w=[int(i) for i in input().split(' ')]
a=[int(i) for i in input().split(' ')]

if len(a)>1:
  l0=abs(a[-1]-a[-2])
else:
  l0=-1000000000000000000
l1=abs(a[-1]-w)

if l1>l0:
  print(l1)
else:
  print(l0)
A, B, C = map(int,input().split())

a = A
b = b
count = 0
if a > b:
    print(0)

while b - a >= 0:
    if count <= C:
        break
    b -= a
    count += 1

print(count)

### FIXED CODE ###

import math

A, B, C = map(int,input().split())

if B - A*C < 0:
    print(math.floor(B/A))
else:
    print(C)
#!/usr/bin/env python
# coding: utf-8
"""
purpose
"""


def main() -> None:
    """
    main function
    """
    (A, B, C, X, Y) = map(int, input().strip().split())

    if 2 * C <= B and 2 * C <= A:
        ans = (max(X, Y) * 2) * C
    elif 2 * C > A:
        ans = Y * 2 * C + max(X - Y, 0) * B
    elif 2 * C > B:
        ans = X * 2 * C + max(Y - X, 0) * A
    else:
        raise ValueError(f"{A}, {B}, {C}")

    print(ans)


if __name__ == "__main__":
    main()


### FIXED CODE ###

#!/usr/bin/env python
# coding: utf-8
"""
purpose
"""


def main() -> None:
    """
    main function
    """
    (A, B, C, X, Y) = map(int, input().split())

    if 2 * C <= A + B:
        ans = C * min(X, Y) * 2 + min(max((X-Y)*A, (Y-X)*B), max(X-Y, Y-X)*C*2)
    else:
        ans = A * X + B * Y

    print(ans)


if __name__ == "__main__":
    main()
x = input()
print(x**3)


### FIXED CODE ###

x = int(input())
print(x**3)
a,b=map(int,input().split())
print("Yes" a=b else "No" )

### FIXED CODE ###

a,b=map(int,input().split())
if a==b:
  print("Yes")
else:
  print("No")
# B Frog 2

n, k = map(int, input().split())
h_list = [int(x) for x in input().split()]

dp = [float('Inf')] * n
dp[0] = 0

for i in range(1,n,1):
    _step = max(0,i-k)
    for j in range(_step,i,1):
        dp[i] = min(dp[i], dp[j] + abs(h_list[i]-h_list[j]))

print(dp[n])

### FIXED CODE ###

# B Frog 2

n, k = map(int, input().split())
h_list = [int(x) for x in input().split()]

dp = [float('Inf')] * n
dp[0] = 0

for i in range(n):
    for j in range(1,k+1,1):
        if i - j < 0:
            continue
        dp[i] = min(dp[i], dp[i-j] + abs(h_list[i-j]-h_list[i]))

        
print(dp[n-1])
a

### FIXED CODE ###

k, s = map(int, input().split())
count = 0

for x in range(k+1):
  for y in range(k+1):
    z = s - x -y
    if z >= 0 and z <= k:
      count += 1

print(count)
a,p=int(input().split())

print(int((a*3+p)/2))

### FIXED CODE ###

import sys
import re
from collections import deque, defaultdict, Counter
from math import ceil, sqrt, hypot, factorial, pi, sin, cos, radians
from itertools import permutations, combinations, product
from operator import itemgetter, mul
from copy import deepcopy
from string import ascii_lowercase, ascii_uppercase, digits
from copy import copy
import numpy as np
from numpy.fft import fft, ifft
from fractions import gcd


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()))


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

a, p = MAP()

print(int((a*3+p)/2))
H, N = map(int, input().split())
ATK = []

for i in range(N):	
  ATK.append(list(map(int, input().split())))
m = min([ATK[i][1] for i in range(N)])
mp_min = [0]
if m < H:
  for hp in range(1, H+1):
    mp_min.append(min([mp_min[max(0, hp-ATK[i][0])] + ATK[i][1] for i in range(N)]))

    #print(mp_min)

  print(mp_min[-1])
else:
  print(min([ATK[i][1] for i in range(N) if ATK[i][0] >= H]))

### FIXED CODE ###

H, N = map(int, input().split())
ATK = []

for i in range(N):	
  ATK.append(list(map(int, input().split())))
mp_min = [0]
for hp in range(1, H+1):
  mp_min.append(min([mp_min[max(0, hp-ATK[i][0])] + ATK[i][1] for i in range(N)]))

 # print(mp_min)

print(mp_min[-1])
#! /usr/bin/python3

N = [int(input()) for N in range(10000)]
#N = 5300
if N % 1000 == 0:
   print(0)
else:
  #N=5300として考えてみる
  ##5300払ったとして5
  sen = N//1000
  ##5*1000=5000円
  sen2 = sen*1000
  ##N(5300)-sen2(5000)
  atai = N-sen2
  #お釣りが300円と出るはずでは？
  print(atai)

### FIXED CODE ###

#! /usr/bin/python3

N = int(input())
1 <= N <= 10000

if N % 1000 == 0:
 print(0)
else:
  sen = N//1000
  sen2 = sen*1000
  atai = N-sen2
  atai2 = 1000-atai
  print(atai2)
def resolve():
    import math
    a, b = map(int, input().split())
    if a == 1:
        bina = 0
    elif a == 2:
        bina = 1
    elif a == 3:
        bina = 3
    elif a%4 ==3:
        bina = a
    else:
        lowera = math.floor((a - 3) / 4) * 4 + 3
        bina = 0
        for i in range(lowera + 1, a):
            bina = bina ^ i

    if b ==1:
        binb = 1
    elif b ==2:
        binb = 3
    elif b==3:
        binb =0
    else:
        if b%4 == 3:
            binb = 0
        else:
            lowerb = math.floor((b-3)/4)*4+3
            binb = 0
        for j in range(lowerb+1, b+1):
            binb = binb^j

    print(bina^binb)
resolve()

### FIXED CODE ###

def resolve():
    import math
    a, b = map(int, input().split())
    if a == 1:
        bina = 0
    elif a == 2:
        bina = 1
    elif a == 3:
        bina = 3
    elif a%4 ==3:
        bina = a
    else:
        lowera = math.floor((a - 3) / 4) * 4 + 3
        bina = 0
        for i in range(lowera + 1, a):
            bina = bina ^ i

    if b ==1:
        binb = 1
    elif b ==2:
        binb = 3
    elif b==3:
        binb =0
    else:
        if b%4 == 3:
            binb = 0
        else:
            lowerb = math.floor((b-3)/4)*4+3
            binb = 0
            for j in range(lowerb+1, b+1):
                binb = binb^j

    print(bina^binb)
resolve()
N = int(input())
A = list(map(int, input().split()))
B = list(map(int, input().split()))

ans, surplus = 0, 0
for i in range(N):
    tmp = min(A[i], surplus)
    ans += tmp
    A[i] -= tmp
    if B[i] > A[i]:
        ans += A[i]
        surplus = B[i] - A[i]
    else:
        ans += B[i]
        surplus = 0
tmp = min(A[N], surplus)
ans += tmp
print(ans)

### FIXED CODE ###

a,b = map(int, input().split())
if (a+b) % 2 == 0:
  print(int((a+b)/2))
else:
  print("IMPOSSIBLE")
def main():
    import math
    def f(m, n, k):
        return int(math.factorial(n-1-m)/(math.factorial(k-1)*math.factorial(n-k-m)))
    n, k = list(map(int, input().split()))
    a = list(map(int, input().split()))
    a = sorted(a)
    # print(a)
    ans = 0
    law = int(pow(10, 9) + 7)
    for i in range(n - k + 1):
        # print(i, n, k)
        # print(f(i, n, k))
        ans += (a[n-1-i] - a[i]) * f(i, n, k)
        ans = ans % law
    print(int(ans))
if __name__ == "__main__":
    main()

### FIXED CODE ###

def main():
    s = input()
    print(chr(ord(s) + 1))
if __name__ == "__main__":
    main()
a = input()
b = input()
l = [1, 2, 3]
l.remove(a)
l.remove(b)
print(l[0])

### FIXED CODE ###

a = int(input())
b = int(input())
l = [1, 2, 3]
l.remove(a)
l.remove(b)
print(l[0])
n, k, q = map(int, input().split())
A = [0]*n
for i in range(n):
  a = int(input())
  A[a-1]+=1
for j in range(n):
  if A[j] > q-k :
    print("Yes")
  else:
    print("No")


### FIXED CODE ###

N, K, Q = map(int, input().split())
A = [0]*N
for i in range(Q):
  a = int(input())
  A[a-1]+=1
for j in range(N):
  if A[j] > Q-K :
    print("Yes")
  else:
    print("No")
n,q=map(int,input().split())
s=list(input())
#print(s)
i=0
a=[]
x=0
while i!=len(s):
    if s[i]=="C" and a1==1:
        x=x+1
        a1=0
    elif s[i]=="A":
        a1=1
    else:
        a1=0
    i=i+1
    a.append(x)
#print(a)
i=0
while i!=q:
  try:
    l,r=map(int,input().split())
    i=i+1
    s=a[r-1]-a[l-1]
    print(s)
  except:
      break

### FIXED CODE ###

n,q=map(int,input().split())
s=list(input())
#print(s)
i=1
a=[0]
x=0
while i!=n:
    if s[i-1]=="A":
        if s[i]=="C":
            x=x+1
    i=i+1
    a.append(x)

#print(a)
i=0
while i!=q:
  try:
    l,r=map(int,input().split())
    i=i+1
    s=a[r-1]-a[l-1]
    print(s)
  except:
      break
N=int(input())
b=list(map(int,input().split()))
if N==1:
    a=[b[0]]*2
elif N==2:
    minb=min(b[0],b[1])
    a=[minb]*2
    a.append(b[-1])    
elif N>2:
    minb=min(b[0],b[1])
    a=[minb]*2
    for i in range(1,N-2):
        minb=min(b[i],b[i+1])
        a.append(minb)
    a.append(b[-1])
print(sum(a))

### FIXED CODE ###

N=int(input())
b=list(map(int,input().split()))
a=b[0]
for i in range(0,N-2):
    a+=min(b[i],b[i+1])
print(a+b[-1])
n,m=list(map(int,input().split()))
par=[i for i in range(n)]
ro=dict()
for i in range(n):
    ro[i]=1
def root(i):
    if par[i]==i:
        return i
    else:
        return root(par[i])

def unite(x,y):
    rx=root(x)
    ry=root(y)
    if rx!=ry:
        par[rx]=ry
        ro[ry]+=ro[rx]
        ro[rx]=0

for i in range(m):
    a,b=list(map(int,input().split()))
    a-=1
    b-=1
    unite(a,b)


# for i in range(n):
#     ro[root(i)]+=1

print(max(ro.values()))

### FIXED CODE ###

n,m=list(map(int,input().split()))
par=[i for i in range(n)]
ro=dict()

for i in range(n):
    ro[i]=1
def root(i):
    if par[i]==i:
        return i
    else:
        a=root(par[i])
        par[i]=a
        return a

def unite(x,y):
    rx=root(x)
    ry=root(y)
    if rx!=ry:
        par[rx]=ry
        ro[ry]+=ro[rx]
        ro[rx]=0

for i in range(m):
    a,b=list(map(int,input().split()))
    a-=1
    b-=1
    unite(a,b)

print(max(ro.values()))
a,b,c=map(int,input().split())
print(min(a,b)*min(max(a,b),c))//2)

### FIXED CODE ###

a,b,c=map(int,input().split())
print(min(a,b)*min(max(a,b),c)//2)
f=lambda:map(int,input().split())
N,M=f()
N+=1;V=[-1]*N
Q=[*range(N)]
F,B=eval('{i:[]for i in Q},'*2)
exec('x,y=f();F[x]+=[y];B[y]+=[x];'*M)
while Q:
 p=Q.pop();S=[1+V[q]for q in B[p]]
 if all(S)and V[p]<0:V[p]=max(S+[0]);Q+=F[p]
print(max(V))

### FIXED CODE ###

from collections import defaultdict
debug = print
def debug(*va): pass

def longest_by_topological_sort(N, nexts, prevs):
    visited = [-1] * N
    max_dist = 0
    que = list(range(N))
    while len(que):
        p = que.pop()
        if visited[p] == -1:
            if all(visited[q] != -1 for q in prevs[p]):
                dist = 0
                for q in prevs[p]:
                    dist = max(dist, visited[q] + 1)
                visited[p] = dist
                max_dist = max(max_dist, dist)
                for n in nexts[p]:
                    que.append(n)
    return max_dist

def test_separate():
    import time
    N = 10**5
    t0 = time.time()
    print(longest_by_topological_sort(N, defaultdict(list), defaultdict(list)))
    print('elapsed', time.time() - t0)

def test_fanout():
    import time
    N = 10**5
    nn, pp = defaultdict(list), defaultdict(list)
    for i in range(1, N):
        nn[0].append(i)
        pp[i].append(0)
    t0 = time.time()
    print(longest_by_topological_sort(N, nn, pp))
    print('elapsed', time.time() - t0)

def test_middle():
    import time
    N = 10**5
    nn, pp = defaultdict(list), defaultdict(list)
    for i in range(1, N):
        # fanout
        nn[0].append(i)
        pp[i].append(0)
        # fanin
        nn[i].append(1)
        pp[1].append(i)
    t0 = time.time()
    print(longest_by_topological_sort(N, nn, pp))
    print('elapsed', time.time() - t0)

if __name__ == '__main__':
    N, M = map(int, input().split())

    nextnodes = [defaultdict(list), defaultdict(list)]
    for i in range(M):
        x, y = map(int, input().split())
        nextnodes[0][x - 1].append(y - 1)
        nextnodes[1][y - 1].append(x - 1)

    max_dist = longest_by_topological_sort(N, nextnodes[0], nextnodes[1])
    print(max_dist)
def main():
    while True:
        n = int(input())
        if n:
            aa,ba = 0,0
            a,b = [None]*n,[None]*n
            for i in range(n):
                a[i],b[i] = map(int, input().split())
                if a[i] > b[i]:
                    aa += (a[i]+b[i])
                elif a[i] < b[i]:
                    ba += (a[i]+b[i])
                else:
                    aa += a[i]
                    ba += b[i]
            print(aa,ba)
        else:
            break

if __name__ == '__main__':
    main()

### FIXED CODE ###

def main():
    while True:
        n = int(input())
        if n:
            aa,ba = 0,0
            a,b = [None]*n,[None]*n
            for i in range(n):
                a[i],b[i] = map(int, input().split())
                if a[i] > b[i]:
                    aa += (a[i]+b[i])
                elif a[i] < b[i]:
                    ba += (a[i]+b[i])
                else:
                    aa += a[i]
                    ba += b[i]
            print(aa,ba)
        else:
            break

if __name__ == '__main__':
    main()
if a%2 == 0:
    print(a)
else:
    print(a*2)

### FIXED CODE ###

a = int(input())

if a % 2 == 0:
    print(a)
else:
    print(a*2)
W, H, x, y = map(int, raw_input().split())
mul = 0
if x*2 == W and y*2 == H:
 mul = 1
A = W * H / 2.0
print '%f %d' % (A, mul)


### FIXED CODE ###

X, A = map(int, raw_input().split())
if X < A:
 print '0'
else:
 print '10'
def main():
    import itertools
    a = list(map(int,input().split()))
    b = list(map(int,input().split()))
    c = list(map(int,input().split()))
    d = [a[0],b[0],c[0]]
    e = [a[1],b[1],c[1]]
    f = [a[2],b[2],c[2]]
    g = [a[0],b[1],c[2]]
    h = [a[2],b[1],c[0]]
    n = int(input())
    listB = [int(input()) for x in range(n)]
    C = itertools.combinations(listB,3)
    if a in C or b in C or c in C or d in C or e in C or f in C or g in C or h in C:
      print("Yes")
    else:
      print("No")
main()

### FIXED CODE ###

def main():
    N = int(input())
    if N%2 == 1:
      print(int((N+1)/2))
    else:
      print(int(N/2))
main()
od = 10**9+7
def comb(n, k):
    c = 1
    for i in range(k):
        c *= n - i
        c %= mod
    d = 1
    for i in range(1, k + 1):
        d *= i
        d %= mod
    return (c * pow(d, mod - 2, mod)) % mod
x,y=map(int,input().split())

ans=0

z=x//2+1

for q in range(z,x+1):
  w=2*q-x
  if w*2+(q-w)==y:
    t=comb(q,w)
    ans+=t
    
  
  
print(ans)

### FIXED CODE ###

mod = 10**9+7
def comb(n, k):
    c = 1
    for i in range(k):
        c *= n - i
        c %= mod
    d = 1
    for i in range(1, k + 1):
        d *= i
        d %= mod
    return (c * pow(d, mod - 2, mod)) % mod
x,y=map(int,input().split())

ans=0

z=x//2

for q in range(z,x+1):
  w=2*q-x
  if w*2+(q-w)==y:
    t=comb(q,w)
    ans+=t
    
  
  
print(ans)
s = inmput()
q = int(ionput())
h,t = [],[]
p = 0

for i in range(q):
    c = input().split()
    if c[0] =='1':
        h,t = t,h
        p = 1-p
    else:
        if c[1] =='1':
            h.append(c[2])
        else:
            t.append(c[2])
if p ==1:
    s = s[::-1]
print("".join(h[::-1])+s+"".join(t))

### FIXED CODE ###

s = input()
q = int(input())
h,t = [],[]
p = 0

for i in range(q):
    c = input().split()
    if c[0] == '1':
        h,t = t,h
        p = 1-p
    else:
        if c[1] =='1':
            h.append(c[2])
        else:
            t.append(c[2])
if p ==1:
    s = s[::-1]
print("".join(h[::-1])+s+"".join(t))
import math
s = int(input())
n = s//3
ans = 0
if n == 0:
    print(0)
else:
    for i in range(n):
        res = s-(3*(i+1))
        fact1 = math.factorial(res+i)
        fact2 = math.factorial(res)
        fact3 = math.factorial(i)
        ans += int(fact1/(fact2*fact3))
    print(ans % (10**9 + 7))

### FIXED CODE ###

import math
s = int(input())
n = s//3
ans = 0
if n == 0:
    print(0)
else:
    for i in range(n):
        res = s-(3*(i+1))
        fact1 = math.factorial(res+i)
        if res == 0:
            fact2 = 1
        else:
            fact2 = math.factorial(res)
        if i == 0:
            fact3 = 1
        else:
            fact3 = math.factorial(i)
        ans += fact1//(fact2*fact3)
    print(ans % (10**9 + 7))