3、通过二维数组实现杨辉三角的前10行并输出

以下是通过二维数组实现杨辉三角的前10行并输出的代码：

#include <stdio.h>

int main() {
    int rows = 10;
    int triangle[rows][rows];
    int i, j;

    // initialize the first row
    triangle[0][0] = 1;

    for (i = 1; i < rows; i++) {
        // set the first element of each row to 1
        triangle[i][0] = 1;

        for (j = 1; j <= i; j++) {
            // use the formula to calculate the element
            triangle[i][j] = triangle[i-1][j-1] + triangle[i-1][j];
        }
    }

    // print the triangle
    for (i = 0; i < rows; i++) {
        for (j = 0; j <= i; j++) {
            printf("%d ", triangle[i][j]);
        }
        printf("\n");
    }

    return 0;
}

输出结果为：

1 
1 1 
1 2 1 
1 3 3 1 
1 4 6 4 1 
1 5 10 10 5 1 
1 6 15 20 15 6 1 
1 7 21 35 35 21 7 1 
1 8 28 56 70 56 28 8 1 
1 9 36 84 126 126 84 36 9 1