# Description

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

For example, given numRows = 5,
Return

[
,
[1,1],
[1,2,1],
[1,3,3,1],
[1,4,6,4,1]
]

The original problem is here.

The original code is here.

# My Solution

I solve this problem in C++, as below:

``````/*Pascal's Triangle
*Author: shuaijiang
*Email: zhaoshuaijiang8@gmail.com
*/
#include<iostream>
#include<vector>
#include<stdlib.h>
using namespace std;

class Solution {
public:
vector<vector<int>> generate(int numRows) {
vector<vector<int>> result;
if(numRows <= 0)
return result;
vector<int> oneRow;
oneRow.push_back(1);
result.push_back(oneRow);
if(numRows == 1)
return result;

for(int i=1;i<numRows;i++){
vector<int> row;
int num = 0;
row.push_back(1);
for(int j=1;j<i;j++){
num = result[i-1][j-1] + result[i-1][j];
row.push_back(num);
}
row.push_back(1);
result.push_back(row);
}
return result;
}
};
``````

# Note:

The number at index i of each row(except the begin and the end) is the sum of the numbers at index i-1 and i of the last row.