Problem:
 Score : 300 points    Problem Statement We have two desks: A and B. Desk A has a vertical stack of N books on it, and Desk B similarly has M books on it.  It takes us A_i minutes to read the i -th book from the top on Desk A (1 \leq i \leq N) , and B_i minutes to read the i -th book from the top on Desk B (1 \leq i \leq M) .  Consider the following action:   Choose a desk with a book remaining, read the topmost book on that desk, and remove it from the desk.   How many books can we read at most by repeating this action so that it takes us at most K minutes in total? We ignore the time it takes to do anything other than reading.      Constraints  1 \leq N, M \leq 200000  1 \leq K \leq 10^9  1 \leq A_i, B_i \leq 10^9  All values in input are integers.         Input Input is given from Standard Input in the following format:  N  M  K  A_1  A_2  \ldots  A_N  B_1  B_2  \ldots  B_M       Output Print an integer representing the maximum number of books that can be read.        Sample Input 1 3 4 240
60 90 120
80 150 80 150      Sample Output 1 3  In this case, it takes us 60 , 90 , 120 minutes to read the 1 -st, 2 -nd, 3 -rd books from the top on Desk A, and 80 , 150 , 80 , 150 minutes to read the 1 -st, 2 -nd, 3 -rd, 4 -th books from the top on Desk B, respectively.  We can read three books in 230 minutes, as shown below, and this is the maximum number of books we can read within 240 minutes.   Read the topmost book on Desk A in 60 minutes, and remove that book from the desk.  Read the topmost book on Desk B in 80 minutes, and remove that book from the desk.  Read the topmost book on Desk A in 90 minutes, and remove that book from the desk.        Sample Input 2 3 4 730
60 90 120
80 150 80 150      Sample Output 2 7       Sample Input 3 5 4 1
1000000000 1000000000 1000000000 1000000000 1000000000
1000000000 1000000000 1000000000 1000000000      Sample Output 3 0  Watch out for integer overflows.

Solution (Python):
N, M, K = map(int, input().split())
A = list(map(int, input().split()))
B = list(map(int, input().split()))
 
ruiseki_A = [0]
ruiseki_B = [0]
 
for i in range(len(A)):
    ruiseki_A.append(ruiseki_A[i]+A[i])
for i in range(len(B)):
    ruiseki_B.append(ruiseki_B[i]+B[i])

 
ans = 0
for i in range(len(ruiseki_A)):
    tmp = K - ruiseki_A[i]
    if tmp < 0:
        continue
    r = len(ruiseki_B)
    l = 0
    while r-l > 1:
        mid = (r + l) // 2
        if ruiseki_B[mid] <= tmp:
            l = mid
        else:
            r = mid
    ans = max(ans, i+l)
 
print(ans)

Solution (Python):
N, M, K = map(int, input().split())
A = list(map(int, input().split()))
B = list(map(int, input().split()))

max_num = 0
j = 0
j_max = M
A_sums=[0]
B_sums=[0]
for i in range(N):
    A_sums.append(A_sums[i]+A[i])
for i in range(M):
    B_sums.append(B_sums[i]+B[i])


for i in range(N + 1):
    j = 0
    if A_sums[i]>K:
        break
    while A_sums[i]+B_sums[j_max] > K:
        j_max -=1

    max_num = max(max_num, i + j_max)
print(max_num)

Solution (Python):
N, M, K = map(int, input().split())
A = list(map(int, input().split()))
B = list(map(int, input().split()))

a, b = [0], [0]

for i in range(N):
  a.append(a[i] + A[i])
for i in range(M):
  b.append(b[i] + B[i])

ans, j = 0, M
for i in range(N + 1):
  if a[i] > K:
    break
  while b[j] > K - a[i]:
    j -= 1
  ans = max(ans, i + j)

print(ans)

Solution (Python):
import bisect
from itertools import accumulate

N , M , K = map(int , input().split())
a = list(map(int , input().split()))
b = list(map(int , input().split()))
a = list(accumulate(a))
b = list(accumulate(b))
a.insert(0,0)

ans = 0
for i in range(N + 1):
    if a[i] > K:
        break
    ans = max(ans , i + bisect.bisect_right(b, K - a[i]))
print(ans)

Solution (Python):

N, M, K = map(int, input().split())
A = list(map(int, input().split()))
B = list(map(int, input().split()))

def isok(bs, RT):
    return True if bs <= RT else False

def search(B, RT):
    left = -1
    right = M+1
    while right-left>1:
        mid = left+(right-left)//2
        if isok(B[mid], RT):
            left = mid
        else:
            right = mid
    return left

def solve():
    asum = [0]*(N+1)
    bsum = [0]*(M+1)
    for i in range(N):
        asum[i+1]=asum[i]+A[i]
    for i in range(M):
        bsum[i+1]=bsum[i]+B[i]

    ans = 0
    for i in range(N+1):
        RT = K-asum[i]
        if RT < 0:
            break
        ans = max(ans, i+search(bsum, RT))
    print(ans)


if __name__ == '__main__':
    solve()

Solution (Python):
import sys
N, M, K = list(map(int, input().split()))

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

a_accum = [0] * (N+1)
b_accum = [0] * (M+1)

for i in range(len(A)):
    a_accum[i+1] = a_accum[i] + A[i]

for j in range(len(B)):
    b_accum[j+1] = b_accum[j] + B[j]


best = 0
j = len(B)
for i in range(len(a_accum)):

    if a_accum[i] > K:
        break

    while b_accum[j] + a_accum[i] > K:
        j -= 1

    best = max(best, i+j)

print(best)