Submission

Score: 100

User: Buslnwzuz

Problemset: ตัวอักษรตัวแรกในคำ

Language: cpp

Time: 0.004 second

Submitted On: 2026-10-10 10:42:49

#include<iostream>
#include <vector>
using namespace std;

int main()
{
    string a;
    cin >> a;
    vector<char> blacklist;
    char first='a';
    bool f;
    for(int i=0;i<a.size();i++){
        for(int j=0;j<a.size();j++){
            if(i==j) continue;
            if(a[i] == a[j]){
                blacklist.push_back(a[j]);
                break;
            }
        }
    }
    for(int j=0;j<a.size();j++){
        f=false;
        for(int i=0;i<blacklist.size();i++){
            if(a[j] == blacklist[i]) f = true;
        }
        if(f) continue;
        if(a[j]<first) first = a[j];
    }
    cout << first;
    return 0;
}