题目描述

blablabla

样例

blablabla

C++ 代码

#include<cstdio>
#include<iostream>
#include<string.h>
#include<vector>
#include<cstring>
#include<algorithm>
#include<math.h>
using namespace std;
int n;
void print(int i){
    int space=(n-i)/2;
    int star=i;
    for (int i = 0; i < space; ++i) {
        cout<<" ";
    }
    for (int i = 0; i < star; ++i) {
        cout<<"*";
    }
    for (int i = 0; i < space; ++i) {
        cout<<" ";
    }
    cout<<endl;

}


int main(){
    cin>>n;
    int flag=1;
    int k=1;
    for (int i = 1; k<=n; k++) {
        print(i);
        if(flag){
            i=i+2;
            flag=(i==n?0:1);

        }
        else{
            i=i-2;
            flag=(i==1?1:0);
        }

    }

    return 0;
}

算法2

(暴力枚举) $O(n^2)$

blablabla

时间复杂度分析：blablabla

C++ 代码

blablabla