题解

#include<iostream>
using namespace std;
int main(){
    int n ;
    cin >> n;
    int sum = 1 ,i = 1 ,cnt = 1;
    while(1){
        if(sum + (i*2+1) * 2  > n ){
            n = n - sum ;
            break;
        }else{
            sum += (i*2+1) * 2 ;
            i++;
            cnt+=2;
        }
    }

	for(int i = 0 ; i < cnt ; i++){
        if(i <= cnt / 2){
            for(int j = 0 ; j < i ; j++){
                cout << " ";
            }
            for(int k = 0 ; k < cnt - 2*i;k++){
                cout <<"*";
            } 
        }else{
            for(int  j=0 ; j < cnt-i-1;j++){
                cout << " ";
            }
            for(int k = 0 ; k < (i+1)*2-cnt ;k++){
                cout <<"*";
            } 
        }
        cout << endl;
    }
   cout << n << endl; ;
    return 0;
}