题解 | 杨辉三角

#include <stdio.h>
#include <stdlib.h>

int main() {
    int n;
    scanf("%d",&n);
    int **a = (int **)malloc(n * sizeof(int *));
    if(a ==NULL){
        printf("error");
        return -1;
    }
    for(int i = 0; i < n; i ++){
        a[i] = (int *)malloc((i + 1) * sizeof(int));
        if(a[i] == NULL){
            printf("error");
            return -1;
        }
        a[i][0] = 1;
        a[i][i] = 1;
    }
    for(int i = 2; i < n; i ++){
        for(int j = 1; j < i; j ++){
            a[i][j] = a[i - 1][j - 1] + a[i - 1][j];
        }
    }
    for(int i = 0; i < n; i ++){
        for(int j = 0; j <= i - 1; j ++){
            printf("%d ",a[i][j]);
        }
        printf("%d\n",a[i][i]);
    }

    return 0;
}