Next Smaller Element

Given an integer array nums, return an integer array counts where counts[i] is the number of smaller elements to the right of nums[i].

Input: [4, 8, 5, 2, 25]
Output: [2, 5, 2, -1, -1]

Input: [13, 7, 6, 12]
Output: [7, 6, -1, -1]
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import java.util.Stack;

public class Solution {

    public static int[] countSmaller(int[] nums) {
       return null;
    }

    public static void main(String[] args) {
        int[] arr = {4, 8, 5, 2, 25};
        int[] nextSmaller = countSmaller(arr);

        for (int i = 0; i < nextSmaller.length; i++) {
            System.out.print(nextSmaller[i] + " ");
        }
    }
}
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public static int[] countSmaller(int[] nums) {
    int[] res = new int[nums.length];
    Stack<Integer> stack = new Stack<>();

    for (int i = nums.length - 1; i >= 0; i--) {
        while (!stack.isEmpty() && stack.peek() >= nums[i]) {
            stack.pop();
        }

        if (stack.isEmpty()) {
            res[i] = -1;
        } else {
            res[i] = stack.peek();
        }
        stack.push(nums[i]);
    }

    return res;
}
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2 5 2 -1 -1
Process finished with exit code 0
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