73 lines
2.0 KiB
Java
73 lines
2.0 KiB
Java
//给你一个整数数组 nums ，找出并返回所有该数组中不同的递增子序列，递增子序列中 至少有两个元素 。你可以按 任意顺序 返回答案。
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//
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// 数组中可能含有重复元素，如出现两个整数相等，也可以视作递增序列的一种特殊情况。
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//
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//
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//
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// 示例 1：
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//
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//
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//输入：nums = [4,6,7,7]
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//输出：[[4,6],[4,6,7],[4,6,7,7],[4,7],[4,7,7],[6,7],[6,7,7],[7,7]]
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//
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//
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// 示例 2：
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//
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//
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//输入：nums = [4,4,3,2,1]
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//输出：[[4,4]]
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//
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//
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//
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//
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// 提示：
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//
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//
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// 1 <= nums.length <= 15
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// -100 <= nums[i] <= 100
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//
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// Related Topics 位运算 数组 哈希表 回溯
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// 👍 319 👎 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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//491:递增子序列
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class IncreasingSubsequences {
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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 IncreasingSubsequences().new Solution();
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System.out.println(solution.findSubsequences(new int[]{4,6,7,7}));
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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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private List<Integer> path = new ArrayList<>();
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private List<List<Integer>> res = new ArrayList<>();
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public List<List<Integer>> findSubsequences(int[] nums) {
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backtracking(nums,0);
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return res;
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}
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private void backtracking (int[] nums, int start) {
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if (path.size() > 1) {
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res.add(new ArrayList<>(path));
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}
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int[] used = new int[201];
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for (int i = start; i < nums.length; i++) {
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if (!path.isEmpty() && nums[i] < path.get(path.size() - 1) ||
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(used[nums[i] + 100] == 1)) continue;
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used[nums[i] + 100] = 1;
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path.add(nums[i]);
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backtracking(nums, i + 1);
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path.remove(path.size() - 1);
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}
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}
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}
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//leetcode submit region end(Prohibit modification and deletion)
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} |