Minimize the Maximum Difference of Pairs

CMakeLists.txt

@@ -316,6 +316,7 @@ add_task(min-cost-climbing-stairs)
 add_task(min-stack)
 add_task(minimize-deviation-in-array)
 add_task(minimize-maximum-of-array)
+add_task(minimize-the-maximum-difference-of-pairs)
 add_task(minimum-absolute-difference-in-bst)
 add_task(minimum-absolute-sum-difference)
 add_task(minimum-ascii-delete-sum-for-two-strings)

solutions/minimize-the-maximum-difference-of-pairs/CMakeLists.txt

@@ -0,0 +1 @@
+add_catch(test_minimize_the_maximum_difference_of_pairs test.cpp)

solutions/minimize-the-maximum-difference-of-pairs/solution.hpp

@@ -0,0 +1,28 @@
+#pragma once
+
+#include <algorithm>
+#include <vector>
+
+class Solution {
+public:
+  int minimizeMax(std::vector<int> nums, int p) {
+    std::sort(nums.begin(), nums.end());
+    int left = 0, right = nums.back() - nums.front();
+    while (left < right) {
+      const auto middle = left + (right - left) / 2;
+      countValidPairs(nums, middle) >= p ? right = middle : left = middle + 1;
+    }
+    return left;
+  }
+
+private:
+  int countValidPairs(const std::vector<int> nums, int threshold) {
+    int cnt = 0;
+    for (size_t i = 0; i + 1 < nums.size(); ++i) {
+      if (nums[i + 1] - nums[i] <= threshold) {
+        ++cnt, ++i;
+      }
+    }
+    return cnt;
+  }
+};

solutions/minimize-the-maximum-difference-of-pairs/test.cpp

@@ -0,0 +1,21 @@
+#include <catch.hpp>
+
+#include <solution.hpp>
+
+TEST_CASE("Simple") {
+  {
+    std::vector<int> nums{10, 1, 2, 7, 1, 3};
+    int p = 2;
+    REQUIRE(1 == Solution().minimizeMax(nums, p));
+  }
+  {
+    std::vector<int> nums{4, 2, 1, 2};
+    int p = 1;
+    REQUIRE(0 == Solution().minimizeMax(nums, p));
+  }
+  {
+    std::vector<int> nums{50};
+    int p = 0;
+    REQUIRE(0 == Solution().minimizeMax(nums, p));
+  }
+}