Pascal's Triangle Leetcode Python Java

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], [1,4,6,4,1]]

Python:

#coding:utf-8class Solution:        def resolve(self,target):                triangle=[]                if(target<=0){                        return triangle                }                for i in range(target):                        sub=[]                        for j in range(0,i+1):                                if j==0 or j==i:                                        sub.append(1)                                else:                                        sub.append(triangle[i-1][j-1]+triangle[i-1][j])                        triangle.append(sub)                return triangle

Java:

java:public class Solution{        public List<List<Integer>> generate(int numRows){                List<List<Integer>> triangle=new ArrayList<List<Integer>>();                if(numRows<=0){                        return triangle;                }                for(int i=0;i<numRows;i++){                        List<Integer> row=new ArrayList<Integer>();                        for(int j=0;j<i+1;j++){                                if(j==0 || j==i){                                        row.add(1);                                }                                               else{                                        row.add(triangle.get(i-1).get(j-1)+triangle.get(i-1).get(j));                                }                        }                        triangle.add(row);                }                return triangle;        }        }