C题求大佬指导，只通过了41%

#include <stdio.h>

#include <stdlib.h>

int main()

{

int n;

scanf("%d",&n);

char *s=(char*)malloc(sizeof(char)*(n+1));

scanf("%s",s);

int zero=0;

int one=0;

int count=0;

int flag=1;

for(int i=0;i<n;i++)//统计0 1

{

if(s[i]=='1')one++;

else zero++;

if(zero-one>0)//101

if(flag==1)//用于说明已经修改过了

{

flag=0;

count=zero;//count为当前前面0的个数，任意修改其一即可

zero--;

one++;

}

else

{

printf("%d",0);//不能取胜

return 0;

}

}

if(flag==0)//修改过

printf("%d",count);

else if(zero==one)printf("%d",zero);

else //zero<one

printf("%d",n);

return 0;

}