2021ccpc中国大学生程序设计竞赛网络选拔赛1009

标记走过点的次数，该点的连续子序列为次数减一
累加即可得到正解

#include<bits/stdc++.h>
#include<string>
using namespace std;
typedef long long ll;
using namespace std;
#define inf 0x3f3f3f3f
const int N=1e5+10;
map<pair<int,int>,int>a;
int main(){

	int n;
	int t;
	scanf("%d",&t);
	while(t--)
	{
		ll sum=0;
    scanf("%d",&n);
    char s[N];
    scanf("%s",s);
     a.clear();
       int x=0,y=0;
       pair<int,int> c(x,y);
       a[c]=1;
	   ll ans=1; 
    for(int i=0;i<n;i++)
    {
    	if(s[i]=='U')
    	{
    		x++;
    		pair<int,int> c(x,y);
    	//cout<<a[c]<<" "<<x<<" "<<y<<" "<<s[i]<<endl;
    	  sum+=a[c]; 
    	  a[c]++; 
		} 
    	if(s[i]=='D')
    	{
    	   	x--;
		pair<int,int> c(x,y);
			//cout<<a[c]<<" "<<x<<" "<<y<<" "<<s[i]<<endl;
	          	sum+=a[c]; 
    	a[c]++; 
		} 
    	if(s[i]=='L')
    	{
    		y--; 
    		pair<int,int> c(x,y);
    			//cout<<a[c]<<" "<<x<<" "<<y<<" "<<s[i]<<endl;
    			sum+=a[c]; 
    	a[c]++; 
    	    
		} 
    	if(s[i]=='R')
    	{
    		y++;
    		pair<int,int> c(x,y);
    		//	cout<<a[c]<<" "<<x<<" "<<y<<" "<<s[i]<<endl;
    		
    	sum+=a[c]; 
    	a[c]++; 
		}	
	}
	cout<<sum<<endl; 

   
}
	return 0;

}