feat(leetcode): 1856. Maximum Subarray Min-Product : 单调栈

Author: upupming

leetcode/残酷刷题/1856. Maximum Subarray Min-Product.js

@@ -0,0 +1,27 @@
+/**
+ * @param {number[]} nums
+ * @return {number}
+ */
+const maxSumMinProduct = function (nums) {
+  const n = nums.length
+  let ans = 0; const sum = []; let s = [-1]; const l = []; const r = []
+  sum[-1] = 0, nums[-1] = nums[n] = -1
+  for (let i = 0; i < n; i++) {
+    sum[i] = sum[i - 1] + nums[i]
+    while (nums[s[s.length - 1]] >= nums[i]) s.pop()
+    l[i] = s[s.length - 1]
+    s.push(i)
+  }
+  s = [n]
+  for (let i = n - 1; i >= 0; i--) {
+    while (nums[s[s.length - 1]] >= nums[i]) s.pop()
+    r[i] = s[s.length - 1]
+    s.push(i)
+  }
+  for (let i = 0; i < n; i++) {
+    // 区间和 [l[i]+1, r[i]-1]
+    const tmp = BigInt(nums[i]) * BigInt(sum[r[i] - 1] - sum[l[i]])
+    if (tmp > ans) ans = tmp
+  }
+  return ans % BigInt(1e9 + 7)
+}

leetcode/残酷刷题/README.md

@@ -85,6 +85,7 @@
 - 316. Remove Duplicate Letters
 - 402. Remove K Digits
 - 42. Trapping Rain Water
+- 1856. Maximum Subarray Min-Product
 
 ### DP