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Record Detail

Accepted


  
# Status Time Cost Memory Cost
#1 Accepted 1ms 320.0 KiB
#2 Accepted 15ms 652.0 KiB
#3 Accepted 26ms 792.0 KiB
#4 Accepted 26ms 592.0 KiB

Code

//* Bismillahir Rahmanir Raheem
#include<bits/stdc++.h>
using namespace std;
typedef vector<int> vi;
typedef long long ll;
typedef unsigned long long ull;
typedef vector<ll> vl;
typedef vector<vi> vvi;
typedef vector<vl> vvl;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef long double ld;
typedef priority_queue<int> PQ;
typedef priority_queue<int, vector<int> , greater<int>> GPQ;
#define bismillah ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define all(a) (a).begin(),(a).end()
#define pb push_back
#define forcin(n) for(auto &x : n) cin >> x
#define forcout(n) for(auto x : n) cout << x << " "
#define sz(n) (int)n.size()
#define YES cout<< "YES\n"
#define NO cout<< "NO\n"
#define RY {cout<< "YES\n";return;}
#define RN {cout<< "NO\n";return;}
#define F first
#define S second
#define el "\n"
#define sp " "
#define mem(a,b) memset(a,b,sizeof(a)) //shudu 0 & -1
#define gcd(a,b) __gcd(a,b)
#define lcm(x, y) x *(y / gcd(x, y))
#define set_pre(a) cout.unsetf(ios::floatfield); cout.precision(a); cout.setf(ios::fixed,ios::floatfield);
#define preci(x) fixed << setprecision(x)
#define ub upper_bound
#define lb lower_bound
#define bs binary_search
#define count_bits(x) __builtin_popcountll(x)
#define clz(x) __builtin_clzll(x)
#define ctz(x) __builtin_ctzll(x)



ll n;

bool ok(ll x){
    x=(x*(x+1))/2;
    x--;
    return x>=n;
}

void solve(){
    cin >> n;
    ll l=0, r=1;
    while(!ok(r))r<<=1ll;
    while(l+1 < r){
        ll m=(l+r)>>1ll;
        if(ok(m)) r=m;
        else l=m;
    }
    if(((r*(r+1))/2)-1 == n){
        cout << 'b' << el;
    }else{
        cout << 'a' << el;
    }
}
int main(){
    bismillah
    int t=1 , tc = 1;
    cin >> t;          
    while(t--){
    //  cout << "Case " << tc++ << ": ";  //! for case
        solve();
    }
    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 15:33:13
Judged At
2026-01-06 15:33:13
Judged By
Score
100
Total Time
26ms
Peak Memory
792.0 KiB