算法习题之 杨辉三角

杨辉三角

/*
思路:
1. 第一层循环控制行数i : 默认[i][0] = 1,[i][i] = 1
2. 第二层循环控制列数j : triangle[i][j] = triangle[i-1][j-1] + triangle[i-1][j]
*/
int **generate(int numRows, int *returnSize) {
    
    *returnSize = numRows;
    
    int **res = (int **)malloc(sizeof(int *) * numRows);
    
    for (int i = 0; i < numRows; i++) {
        res[i] = (int *)malloc(sizeof(int) * (i + 1));
        res[i][0] = 1;
        res[i][i] = 1;
        
        for (int j = 1; j < i; j++) {
            res[i][j] = res[i-1][j] + res[i-1][j-1];
        }
    }
    
    return res;
}

int main(int argc, const char * argv[]) {
    
    printf("杨辉三角问题\n");
    int numRows = 5;
    int returnSize;
    int **returnResult;
    
    returnResult =  generate(numRows, &returnSize);
    for (int i = 0; i < returnSize; i++) {
        printf("[");
        for (int j = 0;  j<=i; j++) {
            printf(" %d ",returnResult[i][j]);
        }
        printf("]\n");
    }
   
    
    return 0;
}