Submission #1666040

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Source Code Expand

#include <bits/stdc++.h>
using namespace std;
int n;
char s[5000020];
int a[5000020];
int f[5000020];
int main() {
	scanf("%d", &n);
	scanf("%s", s + 1);
	for (int i = 1; i <= n; i++) {
		if (s[i] == '1') {
			a[i] = a[i - 1];
		} else {
			a[i] = i;
		}
	}
	for (int i = 1; i <= n; i++) {
		f[i] = f[i - 1];
		if (s[i] == '1') {
			if (s[i - 1] == '0' && s[i - 2] == '1') {
				f[i] = max(f[i], f[a[i - 2]] + i - 2 - a[i - 2]);
				f[i] = max(f[i], f[a[i - 2] + 1] + i - 2 - (a[i - 2] + 1));
			}
			if (s[a[i] - 1] == '1') {
				f[i] = max(f[i], f[a[i] - 2] + i - a[i]);
			}
		}
	}
	printf("%d\n", f[n]);
	return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:8:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &n);
                 ^
./Main.cpp:9:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%s", s + 1);
                    ^

Judge Result