第9周项目3-输出星号图

#include 
using namespace std;
int main()
{
    int a,n,i;
    cout<<"请输入组成直角三角形1的星号行数：";
    cin>>a;
    for (n=1;n<=a;n++)
    {
        for (i=1;i<2*(a-n+1);i++)
            cout<<"*";
        cout<    }
    return 0;
}

#include 
using namespace std;
int main()
{
    int a,n,i,j;
    cout<<"请输入组成直角三角形2的星号行数：";
    cin>>a;
    for (n=1; n<=a; n++)
    {
        for (i=1; i<=a-n; i++)
        {
            cout<<" ";
        }
        for (j=1; j<=n; j++)
        {
            cout<<"*";
        }


        cout<    }
    return 0;
}

#include 
using namespace std;
int main()
{
    int a,n,i,j;
    cout<<"请输入组成三角形3的星号行数：";
    cin>>a;
    for (n=1; n<=a; n++)
    {
        for (i=1; i<=n-1; i++)
        {
            cout<<" ";
        }
        for (j=1; j<=2*(a-n)+1; j++)
        {
            cout<<"*";
        }


        cout<    }
    return 0;
}

#include 
using namespace std;
int main()
{
    int a,n,i,j;
    cout<<"请输入组成三角形4的星号行数：";
    cin>>a;
    for (n=1; n<=a; n++)
    {
        for (i=1; i<=a-n; i++)
        {
            cout<<" ";
        }
        for (j=1; j<=2*n-1; j++)
        {
            cout<<"*";
        }


        cout<    }
    return 0;
}