代码随想录算法训练营day58 739.每日温度 496.下一个更大元素|

题目链接739.每日温度

class Solution {
    public int[] dailyTemperatures(int[] temperatures) {
        int lens = temperatures.length;
        int[] res = new int[lens];
        Deque stack = new LinkedList<>(); 
        stack.push(0);
        for(int i = 1; i  temperatures[stack.peek()]){
                    res[stack.peek()] = i - stack.peek();
                    stack.pop();
                }
                stack.push(i);
            }
        }
        return res;
    }
}

题目链接496.下一个更大元素|

class Solution {
    public int[] nextGreaterElement(int[] nums1, int[] nums2) {
        int lens = nums1.length;
        int[] res = new int[lens];
        Arrays.fill(res, -1);
        Stack stack = new Stack<>();
        stack.add(0);
        HashMap hashMap = new HashMap<>();
        for(int i = 0; i < nums1.length; i++){
            hashMap.put(nums1[i], i);
        }
        for(int i = 1; i < nums2.length; i++){
            if(nums2[i] <= nums2[stack.peek()]){
                stack.add(i);
            }else{
                while(!stack.isEmpty() && nums2[i] > nums2[stack.peek()]){
                    if(hashMap.containsKey(nums2[stack.peek()])){
                        int index = hashMap.get(nums2[stack.peek()]);
                        res[index] = nums2[i];
                    }
                    stack.pop();
                }
                stack.add(i);
            }
        }
        return res;
    }
}