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+// 2289. Steps to Make Array Non-decreasing
+#include "leetcode.h"
+
+/*
+ * given a 0-indexed integer array 'nums'. in one step, remofe all elements
+ * 'nums[i]' where 'nums[i - 1] > nums[i]' for all '0 < i < nums.size()'. return
+ * the number of steps performed until 'nums' becomes non-decreasing
+ */
+
+class Solution {
+public:
+ int totalSteps(vector<int> &nums) {
+ int n = nums.size(), ans = 0;
+ vector<int> stack, dp(n);
+ for (int i = n - 1; i >= 0; --i) {
+ while (!stack.empty() && nums[i] > nums[stack.back()]) {
+ dp[i] = max(++dp[i], dp[stack.back()]);
+ stack.pop_back();
+ ans = max(ans, dp[i]);
+ }
+ stack.push_back(i);
+ }
+ return ans;
+ }
+};
+
+int main() {
+ Solution obj;
+ vector<int> n1 = {5, 3, 4, 4, 7, 3, 6, 11, 8, 5, 11}, n2 = {4, 5, 7, 7, 13};
+ printf("%d\n", obj.totalSteps(n1)); // expect: 3
+ printf("%d\n", obj.totalSteps(n2)); // expect: 0
+}