标签：
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]
]
用上一次生成的array 生成新的array.
Java code:
public List<List<Integer>> generate(int numRows) { List<List<Integer>> result = new ArrayList<List<Integer>>(); for(int i = 0; i < numRows; i++) { List<Integer> arr = new ArrayList<Integer>(); if(result.size() == 0) { arr.add(1); }else { List<Integer> old = result.get(result.size()-1); arr.add(1); for(int j = 0; j < old.size()-1; j++) { arr.add(old.get(j) + old.get(j+1)); } arr.add(1); } result.add(arr); } return result; }
Reference:
1. http://www.programcreek.com/2014/03/leetcode-pascals-triangle-java/
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原文地址：http://www.cnblogs.com/anne-vista/p/4856628.html
