浙江工商大学23机试（打印共底的空心直角三角形）

解法一：直接打印

#include<bits/stdc++.h>
using namespace std;
int main(){
	int n;
	cin>>n;
	for(int i = 0; i < n; i++){
		cout<<"*";
	    for(int j = 1; j < n - 1; j++){
		if(j == i || j == n-1-i || i == n-1 ){
				cout<<"*";
		}else{
			cout<<" ";
			}
		}
		cout<<"*"<<endl;
	}
}

解法二：用二维数组取存储

#include<bits/stdc++.h>
using namespace std;
int main(){
	int n;
	cin>>n;
	vector<vector<string>> a(n,vector<string>(n,"  ")); //初始化为两个空格
	for (int i = 0; i < n; i++){
		a[i][0] = "* ";
		a[i][n-1] = "* ";
	}
	for(int j = 0; j < n; j++){
		a[n-1][j] = "* ";
	} 
	for(int i = 0; i < n; i++){
		for (int j = 0; j < n; j++){
			if(i == j || j == n - 1 - i){
				a[i][j] = "* ";
			}
		}
	}
	for(int i = 0; i < n; i++){
		for (int j = 0; j < n; j++){
			cout<<a[i][j];
		}
		cout<<endl;
	}
}