代码随想录算法训练营第五十八天|739. 每日温度、496.下一个更大元素 I

739. 每日温度

• 刷题https://leetcode.cn/problems/daily-temperatures/description/
• 文章讲解https://programmercarl.com/0739.%E6%AF%8F%E6%97%A5%E6%B8%A9%E5%BA%A6.html
• 视频讲解https://www.bilibili.com/video/BV1my4y1Z7jj/?vd_source=af4853e80f89e28094a5fe1e220d9062

• 题解：

public int[] dailyTemperatures(int[] T) {
    int length = T.length;
    int[] result = new int[length];

    for (int i = 0; i < length; i++) {
        int current = T[i];
        if (current < 100) {
            for (int j = i + 1; j < length; j++) {
                if (T[j] > current) {
                    result[i] = j - i;
                    break;
                }
            }
        }
    }

    return result;
}

496.下一个更大元素 I

• 刷题https://leetcode.cn/problems/next-greater-element-i/description/
• 文章讲解https://programmercarl.com/0496.%E4%B8%8B%E4%B8%80%E4%B8%AA%E6%9B%B4%E5%A4%A7%E5%85%83%E7%B4%A0I.html
• 视频讲解https://www.bilibili.com/video/BV1jA411m7dX/?vd_source=af4853e80f89e28094a5fe1e220d9062

• 题解：

public class Solution {
    public int[] nextGreaterElement(int[] nums1, int[] nums2) {
        int len1 = nums1.length;
        int len2 = nums2.length;
        Deque<Integer> stack = new ArrayDeque<>();
        Map<Integer, Integer> map = new HashMap<>();
        for (int i = 0; i < len2; i++) {
            while (!stack.isEmpty() && stack.peekLast() < nums2[i]) {
                map.put(stack.removeLast(), nums2[i]);
            }
            stack.addLast(nums2[i]);
        }
        int[] ans = new int[len1];
        for (int i = 0; i < len1; i++) {
            ans[i] = map.getOrDefault(nums1[i], -1);
        }
        return ans;
    }
}