Pascal's Triangle

Given numRows, generate the first numRows of Pascal's triangle.

For example, given numRows = 4,
Return

[    [1],
    [1,1],
   [1,2,1],
  [1,3,3,1] ]

C program : 

int** generate(int numRows, int** columnSizes) {
    int i, j;
    int numColumns = 0;
    *columnSizes = malloc(numRows*sizeof(int));
    int** result = (int**)malloc(numRows*sizeof(int*));
   
    for (i = 0; i < numRows; i++)
        result[i] = (int*)malloc((i+1)*sizeof(int));
   
    for (i = 0; i < numRows; i++) {
       
        result[i][0] = result[i][i] = 1;
        for (j = 0; j < i; j++) {
         result[i][j] = result[i-1][j-1] + result[i-1][j];
        }
        numColumns++;
        *(*columnSizes+i) = numColumns;
    }
    return result;
}


C++ program : 

class Solution {
public:
    vector<vector<int>> generate(int numRows) {
        vector<vector<int>>result(numRows);
        for (int i = 0; i < numRows; i++) {
            result[i].resize(i+1);
            result[i][0] = result[i][i] = 1;
            for (int j = 0; j < i ; j++) {
                result[i][j] = result[i-1][j-1] + result[i-1][j];
            }
        }
       
        return result;
    }
};