import java.util.ArrayList;import java.util.Arrays;import java.util.List;/** * Source : https://oj.leetcode.com/problems/pascals-triangle/ * * * 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] * ] * * */public class PascalTiangle {    /**     * 生成杨辉三角（帕斯卡三角形）     *     * @param n     * @return     */    public List
    
     
      > generate (int n) {        List
      
       
        > result = new ArrayList
        
         
          >(n); if (n == 0) { return result; } result.add(Arrays.asList(new Integer[]{1})); for (int i = 2; i <= n; i++) { List
          
            list = new ArrayList
           
            (i); list.add(1); for (int j = 1; j < i-1; j++) { list.add(result.get(i-2).get(j-1) + result.get(i-2).get(j)); } list.add(1); result.add(list); } return result; } public void print (List
            
             
              > list) { for (int i = 0; i < list.size(); i++) { for (int j = 0; j <= list.size() - i; j++) { System.out.print(" "); } System.out.println(Arrays.toString(list.get(i).toArray(new Integer[list.get(i).size()]))); } } public static void main(String[] args) { PascalTiangle pascalTiangle = new PascalTiangle(); pascalTiangle.print(pascalTiangle.generate(5)); }}