C++ 沙漏图案（Hour-glass Pattern）

本文链接：https://blog.youkuaiyun.com/hefeng_aspnet/article/details/140601556

给定正整数 n，以沙漏形式打印数字模式。
示例：

输入：rows_no = 7

输出：

1 2 3 4 5 6 7
2 3 4 5 6 7
3 4 5 6 7
4 5 6 7
5 6 7
6 7
7
6 7
5 6 7
4 5 6 7
3 4 5 6 7
2 3 4 5 6 7
1 2 3 4 5 6 7

// CPP code for hour glass
// pattern.

#include <iostream>
using namespace std;

// Function definition
void pattern(int rows_no)
{
int i, j, k;

// for loop for printing
// upper half
for (i = 1; i <= rows_no; i++) {

// printing i spaces at
// the beginning of each row
for (k = 1; k < i; k++)
cout << " ";

// printing i to rows value
// at the end of each row
for (j = i; j <= rows_no; j++)
cout << j << " ";

cout << endl;
}

// for loop for printing lower half
for (i = rows_no - 1; i >= 1; i--) {

// printing i spaces at the
// beginning of each row
for (k = 1; k < i; k++)
cout << " ";


// printing i to rows value
// at the end of each row
for (j = i; j <= rows_no; j++)
cout << j << " ";

cout << endl;
}
}

// Driver code
int main()
{
// taking rows value from the user
int rows_no = 7;

pattern(rows_no);
return 0;
}