Problem: N people are arranged in a row from left to right.  You are given a string S of length N consisting of `0` and `1`, and a positive integer K.  The i-th person from the left is standing on feet if the i-th character of S is `0`, and standing on hands if that character is `1`.  You will give the following direction at most K times (possibly zero):  **Direction** : Choose integers l and r satisfying 1 \leq l \leq r \leq N, and flip the l-th, (l+1)-th, ..., and r-th persons. That is, for each i = l, l+1, ..., r, the i-th person from the left now stands on hands if he/she was standing on feet, and stands on feet if he/she was standing on hands.  Find the maximum possible number of **consecutive** people standing on hands after at most K directions.

Submission attempts (in order):
n, k = map(int,input().split())
s = input()

ns = []
now_num = s[0]
cnt = 0
for i in range(n):
    if now_num == s[i]:
        cnt += 1
    else:
        ns.append((now_num, cnt))
        now_num = s[i]
        cnt = 1
ns.append((now_num, cnt))
#print(ns)
len_ns = len(ns)
pre = [0] * (len_ns + 1)
for i in range(len_ns):
    pre[i + 1] = pre[i] + ns[i][1]
#print(pre)

ans = 1
for i in range(len_ns - 2*k + 1):
    temp = pre[i + 2*k] - pre[i]
    if ns[i - 1][0] == '1':temp += ns[i - 1][1]
    elif i + 2*k != len_ns and ns[i + 2*k][0] == '0':temp += ns[i + 2*k][1]
    if temp > ans:ans = temp
print(ans if len_ns - 2*k + 1 > 0 else len(s))

n, k = map(int,input().split())
s = input()

ns = []
now_num = s[0]
cnt = 0
for i in range(n):
    if now_num == s[i]:
        cnt += 1
    else:
        ns.append((now_num, cnt))
        now_num = s[i]
        cnt = 1
ns.append((now_num, cnt))
#print(ns)
len_ns = len(ns)
pre = [0] * (len_ns + 1)
for i in range(len_ns):
    pre[i + 1] = pre[i] + ns[i][1]
#print(pre)

ans = 1
for i in range(len_ns - 2*k + 1):
    temp = pre[i + 2*k] - pre[i]
    if ns[i - 1][0] == '1':temp += ns[i - 1][1]
    elif i + 2*k != len_ns and ns[i + 2*k][0] == '0':temp += ns[i + 2*k + 1][1]
    if temp > ans:ans = temp
print(ans if len_ns - 2*k + 1 > 0 else len(s))

n, k = map(int,input().split())
s = input()

ns = []
now_num = s[0]
cnt = 0
for i in range(n):
    if now_num == s[i]:
        cnt += 1
    else:
        ns.append((now_num, cnt))
        now_num = s[i]
        cnt = 1
ns.append((now_num, cnt))
len_ns = len(ns)
pre = [0] * (len_ns + 1)
for i in range(len_ns):
    pre[i + 1] = pre[i] + ns[i][1]
print(ns)
print(pre)

ans = 1
for i in range(len_ns - 2*k + 1):
    temp = pre[i + 2*k] - pre[i]
    if i > 0 and ns[i - 1][0] == '1':temp += ns[i - 1][1]
    if i + 2*k < len_ns and ns[i + 2*k][0] == '1':temp += ns[i + 2*k][1]
    if temp > ans:ans = temp
print(ans if len_ns - 2*k + 1 > 0 else len(s))

n, k = map(int,input().split())
s = input()

ns = []
now_num = s[0]
cnt = 0
for i in range(n):
    if now_num == s[i]:
        cnt += 1
    else:
        ns.append((now_num, cnt))
        now_num = s[i]
        cnt = 1
ns.append((now_num, cnt))
len_ns = len(ns)
pre = [0] * (len_ns + 1)
for i in range(len_ns):
    pre[i + 1] = pre[i] + ns[i][1]

ans = 1
for i in range(len_ns - 2*k + 1):
    temp = pre[i + 2*k] - pre[i]
    if i > 0 and ns[i - 1][0] == '1':temp += ns[i - 1][1]
    if i + 2*k < len_ns and ns[i + 2*k][0] == '1':temp += ns[i + 2*k][1]
    if temp > ans:ans = temp
print(ans if len_ns - 2*k + 1 > 0 else len(s))

Verdicts: Wrong Answer

Runtime Error

Wrong Answer

Accepted