牛客练习赛58 B 牛妹和01串 - 贪心

从左到右扫一遍贪心，能分割就分割

#include <bits/stdc++.h>
using namespace std;

const int N = 1000005;
int n,ans;
char s[N];

signed main() {
    cin>>s+1;
    n=strlen(s+1);
    int flag=0;
    for(int i=1;i<=n;i++) {
        if(s[i]=='0') flag|=1;
        if(s[i]=='1') flag|=2;
        if(flag==3) {
            flag=0;
            ++ans;
        }
    }
    cout<<ans;
}