Osajono

input/code.cpp: In function 'int main()':
input/code.cpp:17:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < input.length(); i++) {
                    ^

#include <iostream>
#include <algorithm>
#include <unordered_map>
#define ll long long
using namespace std;

int main() {
	ios_base::sync_with_stdio(0);
	
	unordered_map<char, int> best;
	
	string input;
	cin >> input;
	
	ll count = 0;
	
	for (int i = 0; i < input.length(); i++) {
		count += best[input[i]];
		if (best.count(input[i])) {
			best[input[i]] = best[input[i]]+1;
		}
		
	}
	
	cout << count+input.length() << '\n';
	
	
	
	return 0;
}	

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 1

Verdict: ACCEPTED

Test 3

Group: 1

Verdict: ACCEPTED

Test 4

Group: 1

Verdict: ACCEPTED

Test 5

Group: 1

Verdict: ACCEPTED

Test 6

Group: 2

Verdict: ACCEPTED

Test 7

Group: 2

Verdict: ACCEPTED

Test 8

Group: 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: ACCEPTED

Test 10

Group: 2

Verdict: ACCEPTED

Test 11

Group: 3

Verdict: ACCEPTED

Test 12

Group: 3

Verdict: ACCEPTED

Test 13

Group: 3

Verdict: ACCEPTED

Test 14

Group: 3

Verdict: ACCEPTED

Test 15

Group: 3

Verdict: ACCEPTED