Sock Merchant

1. 문제

2. 알고리즘

키워드 - 구현

3. 코드

#include <bits/stdc++.h>
 
using namespace std;
 
int sockMerchant(int n, vector <int> ar) {
    // Complete this function
    
    map<int, int> m;
 
    for(int i = 0; i < n; i++) {
        //cout << ar[i] << endl;
        m[ar[i]]++;
    }
 
    map<int, int>::iterator iter;
 
    int sol = 0;
    for(iter = m.begin(); iter != m.end(); ++iter) {
 
        //cout << iter->first << " " << iter->second << endl;
 
        int value = iter->second ;
        if(value >= 2) {
            int cand = iter->second / 2;
            sol = sol + cand;
        }
    }
 
    return sol;
}
 
int main() {
    int n;
    cin >> n;
    vector<int> ar(n);
    for(int ar_i = 0; ar_i < n; ar_i++){
       cin >> ar[ar_i];
    }
    int result = sockMerchant(n, ar);
    cout << result << endl;
    return 0;
}