Codeforces Round #409 (Div. 2) A. Vicious Keyboard

题目链接：Vicious Keyboard

题目大意：给一串只包含V和K的字符，最多替换一次V为K或者K为V，问字符串中最多能出现多少次VK

题目思路：这题都没能一次AC啊，真菜，直接算出来最开始有多少个V看，然后遍历整个字符串，把V替换成K，K替换成V再算，每次求最大值就可以了

#include <bits/stdc++.h>using namespace std;typedef long long ll;int solve(string s){    int res = 0;    for(int i = 1;i <= s.size();i++){        if(s[i-1] == 'V'&&s[i] == 'K') res++;    }    return res;}int main(){    ios::sync_with_stdio(false);    string s;    cin>>s;    int ans = solve(s);    for(int i = 0;i < s.size();i++){        string cur = s;        if(cur[i] == 'V') cur[i] = 'K';        else cur[i] = 'V';        ans = max(ans,solve(cur));    }    cout<<ans<<endl;    return 0;}