#include<iostream>
using namespace std;
void DrawTri();
void DrawDia();
int main()
{
    int type=0;
    cout<<"选择你需要的图形：\n";
    cout<<"   1.三角形\n";
    cout<<"   2.菱形\n";
    cin>>type;
    while(!(cin.good()&&type==1||type==2))
    {
        cin.clear();
        cin.ignore(1024,'\n');
        cout<<"输入的图形类型不正确请重新输入：\n";
        cin>>type;
    }
    switch(type)
    {
    case 1:
        DrawTri();
        break;
    case 2:
        DrawDia();
        break;
    default:
        cout<<"输入的图形类型不正确请重新输入：\n";
        break;
    }
    return 0;
}
void DrawTri()
{
    int layer=0;
    cout<<"输入层数:\n";
    cin>>layer;
    while(!(cin.good()&&layer>1))
    {
        cin.clear();
        cin.ignore(1024,'\n');
        cout<<"输入的层数不正确或输入的层数小于2请重新输入：\n";
        cin>>layer;
    }
    cout<<layer<<"层三角形：\n";
    for(int i=1;i<=layer;i++)
    {
        for(int j=1;j<=(layer-i);j++)
        {
            cout<<" ";
        }
        for(int k=1;k<=2*(i-1)+1;k++)
        {
            cout<<"*";
        }
        cout<<"\n";
    }
}
 void DrawDia()
 {
    int layer = 0;
    //记录中间层
    int mid;
   
    cout<<"输入层数：\n";
    cin>>layer;
    while(!(cin.good() && layer > 3 && (layer%2 != 0))) {
            cin.clear();
            cin.ignore(1024,'\n');
            cout<<"输入的层数类型不正确或层数小于3或层数不为基数,请重新输入：\n";
            cin>>layer;
    }
   
    mid = (layer + 1)/2;
   
    cout<<layer<<"层菱形：\n";
    for(int i = 1; i <= layer; i++) {
        int j;
        
        for(j = 1;j <= abs(i - mid); j++) {
            cout<<" ";
        }
        for(int k = 1; k <= (mid - j) * 2 + 1; k++) {
            cout<<"*";
        }
   
        cout<<"\n";
    }
}

...

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