백준 10809번: 알파벳 찾기 (C++)

https://www.acmicpc.net/problem/10809

#pragma warning(disable :4996)
#include<iostream>
#include<string>
using namespace std;
int alp[26];
int main(void) {
    //ios::sync_with_stdio(false);
    cin.tie(0);
    
    string str;
    cin >> str;
 
    for (int i = 0; i < 26; i++)
        alp[i] = -1;
    for (int i = 0; i < str.length(); i++) {
        if (alp[str[i] - 'a'] == -1)
            alp[str[i] - 'a'] = i;
    }
    for (int i = 0; i < 26; i++)
        if (alp[i] >= 0) cout << alp[i] << ' ';
        else
            cout << -1 << ' ';
 
    return 0;
}