hihocoder1543 SCI表示法

#include <bits/stdc++.h>
#define ll long long
#define maxn 100100
using namespace std;
ll a[maxn];
int main(){
    ll T,n;
    cin>>T;
    for(ll i=1;i<=100010;i++) a[i] = i*(i+1)/2;
    while(T--){
        cin>>n;
        ll l=0,r=100001,ans=-1,mid;
        while(l<=r){
            mid = (l+r)>>1;
            if(a[mid]<=n) ans = mid,l = mid+1;
            else r = mid-1;
        }
        if(a[ans] == n) cout<<ans<<endl;
        else{
            for(ll i=ans;i>=1;i--){
                if((n-a[i])%i == 0){
                    cout<<i<<endl;
                    break;
                }
            }
        }
    }
    return 0;
}