/**

* Created by Corn on 12/19/14.

*

*

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

For example, given numRows = 5,

Return

[

[1],

[1,1],

[1,2,1],

[1,3,3,1], //a[i] = result[i-1][i-1]+result[i-1][i]

[1,4,6,4,1]

]

*

*/

//ac 146ms

function pascalTriangle(numRows){

if(numRows == 0) {

return [];

}

if(numRows == 1) {

return [[1]];

}

var result = [];

//build the first list

var firstRow = [1];

result.push(firstRow);

for(var i = 1; i< numRows; i++){

var row = [1]; // add first element

var temp = result[i-1];

var size = temp.length;

for(var j = 1; j< size; j++){

row.push(temp[j-1]+temp[j]);

}

row.push(1);

console.log(row);

result.push(row);

}

return result;

}

console.log(pascalTriangle(7));