59 lines
1.4 KiB
Java
59 lines
1.4 KiB
Java
//给定一个非负整数 numRows，生成杨辉三角的前 numRows 行。
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//
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//
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//
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// 在杨辉三角中，每个数是它左上方和右上方的数的和。
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//
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// 示例:
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//
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// 输入: 5
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//输出:
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//[
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// [1],
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// [1,1],
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// [1,2,1],
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// [1,3,3,1],
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// [1,4,6,4,1]
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//]
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// Related Topics 数组 动态规划
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// 👍 525 👎 0
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package leetcode.editor.cn;
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import java.util.ArrayList;
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import java.util.List;
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//118:杨辉三角
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public class PascalsTriangle{
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public static void main(String[] args) {
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//测试代码
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Solution solution = new PascalsTriangle().new Solution();
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}
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//力扣代码
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//leetcode submit region begin(Prohibit modification and deletion)
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class Solution {
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public List<List<Integer>> generate(int numRows) {
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List<List<Integer>> result = new ArrayList<>();
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for (int i = 0; i < numRows; i++) {
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List<Integer> list = new ArrayList<>();
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if(i==0){
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list.add(1);
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result.add(list);
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continue;
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}
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List<Integer> bef = result.get(i-1);
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for (int j = 0; j <= i; j++) {
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if(j==0||j==i){
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list.add(1);
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}else{
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list.add(bef.get(j-1)+ bef.get(j));
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}
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}
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result.add(list);
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}
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return result;
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}
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}
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//leetcode submit region end(Prohibit modification and deletion)
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} |