Submission #8729957

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Source Code Expand

#include <bits/stdc++.h>
using namespace std;



long long mod = 1000000007;



bool one[10];
bool two[100];
bool three[1000];
int main(){
	//freopen("i.txt","r",stdin);
	
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	int n;
	cin >> n;
	string s;
	cin >> s;
	for(int i = 0;i < n;i++){
		int x = (s[i] - '0');
		
		
		for(int j = 0;j < 100;j++){
			if(two[j]){
				three[j*10+x] = true;
			}
		}
		
		for(int j = 0;j < 10;j++){
			if(one[j]){
				two[j*10+x] = true;
			}
		}
		
		one[x] = true;
	} 
	int ans = 0;
	for(int i = 0;i < 1000;i++){
		if(three[i]) ans++;
	}
	cout << ans;
	
}

Submission Info

Judge Result