1027 打印沙漏

题目 

#include<iostream>
#include<cmath>
using namespace std;
int main() {
	int k=0,i,j,n;
	char c;
	cin>>n>>c;
	while(1) {
		if((2*pow(k+1,2)-1)>n)break;
		else k++;
	}
	for(i=k-1; i>0; i--) {
		for(j=1; j<=(k-1-i); j++)cout<<" ";
		for(j=1; j<=(2*i+1); j++)cout<<c;
		cout<<endl;
	}
	for(i=0; i<=k-1; i++) {
		for(j=1; j<=(k-1-i); j++)cout<<" ";
		for(j=1; j<=(2*i+1); j++)cout<<c;
		cout<<endl;
	}//cout<<k-1<<endl;
	cout<<(n-2*pow(k,2)+1)<<endl;
	return 0;
}