Rock-Paper-Scissors

Posted 2020-09-30

/*
Author: 2486
Memory: 0 KB		Time: 31 MS
Language: GNU G++ 4.9.2		Result: Accepted
Public:		No Yes

*/
//对于存在一定的极少区间段而言。能够使用前辍和进行标记，使得达到查找接近O(n)
#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;
const int maxn=1000+5;
int T,n;
int R[2][maxn],S[2][maxn],P[2][maxn];
char str[maxn];
int Compare(char x,char y) {
    if(x=='P'&&y=='R'||x=='S'&&y=='P'||x=='R'&&y=='S') {
        return 1;
    }
    if(x==y)return 2;
    return 0;
}
int main() {
    //freopen("D://imput.txt","r",stdin);
    scanf("%d",&T);
    while(T--) {
        memset(R,0,sizeof(R));
        memset(S,0,sizeof(S));
        memset(P,0,sizeof(P));
        scanf("%d%s",&n,str);
        for(int i=0; i<n; i++) {
            R[0][i+1]=R[0][i];
            R[1][i+1]=R[1][i];
            P[0][i+1]=P[0][i];
            P[1][i+1]=P[1][i];
            S[0][i+1]=S[0][i];
            S[1][i+1]=S[1][i];
            if(Compare('R',str[i])==1) {
                R[0][i+1]=R[0][i]+1;
            } else if(Compare('R',str[i])==0) {
                R[1][i+1]=R[1][i]+1;
            }
            if(Compare('P',str[i])==1) {
                P[0][i+1]=P[0][i]+1;
            } else if(Compare('P',str[i])==0){
                P[1][i+1]=P[1][i]+1;
            }
            if(Compare('S',str[i])==1) {
                S[0][i+1]=S[0][i]+1;
            } else if(Compare('S',str[i])==0){
                S[1][i+1]=S[1][i]+1;
            }
        }
        int cnt=0;
        for(int i=0; i<=n; i++) {
            for(int j=i; j<=n; j++) {
                if(R[0][i]+P[0][j]-P[0][i]+S[0][n]-S[0][j]-R[1][i]-(P[1][j]-P[1][i])-(S[1][n]-S[1][j])>0) {
                    cnt++;
                    //printf("[%d,%d]\n",i,j);
                }
            }
        }
        printf("%d\n",cnt);
    }
    return 0;
}