题解 | Flower_Rainbow_and_Balloon

#include <iostream>
using namespace std;

int main() {
    int tt; cin >> tt;
    while(tt--){
        int n,m; cin >> n >> m;
        long long k; cin >> k;
        string s; cin >> s;

        int cnt_r=0,cnt_y=0,cnt_w=0,min_=1000009;
        int l=0;
        bool ok=false;
        for(int r=0;r<n;r++){
            if(s[r]=='r') cnt_r++;
            else if(s[r]=='y') cnt_y++;
            else cnt_w++;
            long long score=2*max(cnt_r,cnt_y)+min(cnt_r,cnt_y)+2*min(m,cnt_w);

            while(score>=k && l<=r){
                min_ = min(min_, r-l+1);
                ok=true;

                if(s[l]=='r') cnt_r--;
                else if(s[l]=='y') cnt_y--;
                else cnt_w--;
                
                l++;
                
                
                score = 2*max(cnt_r,cnt_y)+min(cnt_r,cnt_y)+2*min(m,cnt_w);
                
            }
        }
        if(ok) cout << min_ << endl;
        else cout << -1 << endl;
    }
}