Codeforces Round #409 (rated, Div. 2, based on VK Cup 2017 Round 2) A. Vicious Keyboard

改一次最多增加一个，遍历一遍即可

#include<bits/stdc++.h>using namespace std;char s[105];int cnt=0,flag=0;int main(){    cin>>s;    for(int i=0;i<strlen(s)-1;i++)    {        if(s[i]=='V'&&s[i+1]=='K')cnt++,i++;        else if(s[i+1]=='K'||(s[i]=='V'&&s[i+2]!='K'))flag=1;    }    cout<<cnt+flag;    return 0;}