Sanalista

input/code.cpp: In function 'bool even(std::__cxx11::string&, char&)':
input/code.cpp:11:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i = 0; i < s.size(); i++)
                     ~~^~~~~~~~~~

#include <bits/stdc++.h>

using namespace std;

string s;
int o = 0;

bool even(string& s, char& c) {
    int k = 0;

    for (int i = 0; i < s.size(); i++)
        if (s[i] == c) k++;

    return k%2 == 0;
}

int main() {

    getline(cin, s);
    int l = stoi(s);

    for (int i = l; i > 0; i--) {
        cin >> s;

        for (char& c : s) {
            if (!even(s, c)) {
                o++;
                break;
            }
        }
    }

    cout << l-o << "\n";
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED