/ SeriousOJ /

Record Detail

Accepted


  
# Status Time Cost Memory Cost
#1 Accepted 1ms 404.0 KiB
#2 Accepted 11ms 648.0 KiB
#3 Accepted 17ms 532.0 KiB
#4 Accepted 36ms 532.0 KiB

Code

#include <iostream>
#include <vector>
#include <cmath>
#include <numeric>
#include <algorithm>
#include <set>
#include <unordered_set>
#include <cstring>
#include <unordered_map>
#include <iomanip>
#include <queue>
#include <map>
#include <sstream>
#include <stack>
#include <bitset>
#include <random>

using ll = long long;

using namespace std;

void solve() {
    ll k;
    cin >> k;

    // n^2 + 3n - 2k = 0
    ll delta = 9ll + 8ll * k;
    ll sdelta = sqrt(delta) + 1e-9;
    if (sdelta * sdelta != delta) {
        cout << "a\n";
    } else {
        cout << "b\n";
    }
}

int main() {
    #ifdef LOCAL
    freopen("input.txt", "r", stdin);
    // freopen("output.txt", "w", stdout);
    #endif
    ios::sync_with_stdio(0);
    cin.tie(0);
    int t;
    cin >> t;
    while (t--) solve();
}

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 15:05:43
Judged At
2026-01-06 15:05:44
Judged By
Score
100
Total Time
36ms
Peak Memory
648.0 KiB