1463：[蓝桥杯2019初赛]年号字串

//1463: [蓝桥杯2019初赛]年号字串
#include <iostream>
#include <algorithm>
using namespace std;
char al[26] = {'A', 'B', 'C', 'D', 'E', 'F', 'G', 
'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 
'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'};
int main(){
    int n = 2019;
    int a;
    string ans;
    while(n > 26){
        a = n % 26;
        ans += al[a-1];
        n /= 26; 
    }
    ans += al[n-1]; 
    reverse(ans.begin(), ans.end());
    cout<<ans;
    return 0;
}