【思维】构造——ICPC NEAU B

#include<bits/stdc++.h>
using namespace std;
#define N 200005
#define ll long long

ll n,m,a[N];

int main(){
    int t;cin>>t;
    while(t--){
        cin>>n>>m;
        for(int i=1;i<=n;i++){
            if(m>=n-i){
                a[i]=1;m-=n-i;
            }else {//m<n-i
                ll len=10000,p=n+1;
                while(i<=n){
                    while(len*(len-1)/2>m)len--;
                    for(int j=i;j<=i+len-1;j++)
                        a[j]=p;
                    p++;
                    m-=len*(len-1)/2;
                    i=i+len;
                }
            }
        }
        for(int i=1;i<=n;i++)cout<<a[i]<<‘ ‘;
        puts("");
    }
}