/ SeriousOJ /

Record Detail

Accepted


  
# Status Time Cost Memory Cost
#1 Accepted 1ms 532.0 KiB
#2 Accepted 16ms 532.0 KiB
#3 Accepted 24ms 532.0 KiB
#4 Accepted 25ms 692.0 KiB

Code

#include <bits/stdc++.h>
using namespace std;

#define vi vector<int>
#define PB push_back
#define vll vector<long long>
#define ll long long
#define all(x) x.begin(), x.end()
#define F first
#define S second
#define ld long double
#define vld vector<long double>

const ll mod = 998244353;
const ll MOD = 1e9 + 7;

ll sum(ll n){
    return (n * (n + 1)) / 2ll;
}

void solve(int tst){
    
    ll x;
    cin >> x;

    ll l = 0, r = 1e8;

    while (l < r - 1){
        ll mid = l + (r - l) / 2;
        ll pod = sum(mid) + mid;
        if (pod < x) l = mid;
        else r = mid;
    }

    if (sum(r) + r == x){
        cout << "b\n";
    }
    else {
        cout << "a\n";
    }

}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    // pre();
    int tc = 1;
    cin >> tc;
    for (int i = 1; i <= tc; i++){
        solve(i);
    }
    return 0;
}

Information

Submit By
Type
Submission
Problem
P1223 C. Infinity Sequence
Contest
Happy New Year 2026
Language
C++17 (G++ 13.2.0)
Submit At
2026-01-06 15:34:09
Judged At
2026-01-06 15:34:09
Judged By
Score
100
Total Time
25ms
Peak Memory
692.0 KiB