add: 220211

2202/220211-CN.cpp

@@ -0,0 +1,25 @@
+#include <algorithm>
+#include <vector>
+
+/**
+ * 1984. Minimum Difference Between Highest and Lowest of K Scores
+ * You are given a 0-indexed integer array nums, where nums[i] represents the score of the ith student. You are also given an integer k.
+ * Pick the scores of any k students from the array so that the difference between the highest and the lowest of the k scores is minimized.
+ * Return the minimum possible difference.
+ */
+
+class Solution {
+public:
+	int minimumDifference(std::vector<int>& nums, int k) {
+		std::sort(nums.begin(), nums.end());
+		int ans = 99999999;
+		for (int i = k; i <= nums.size(); ++i)
+			ans = std::min(ans, nums[i - 1] - nums[i - k]);
+		return ans;
+	}
+};
+
+int main() {
+	// Submitted by phone, no test provided.
+	return 0;
+}

2202/220211.cpp

@@ -0,0 +1,32 @@
+#include <string>
+
+/**
+ * 567. Permutation in String
+ * Given two strings s1 and s2, return true if s2 contains a permutation of s1, or false otherwise.
+ * In other words, return true if one of s1's permutations is the substring of s2.
+ */
+
+class Solution {
+private:
+	bool ok(int* c) {
+		for (int i = 0; i < 26; ++i)
+			if (c[i]) return false;
+		return true;
+	}
+public:
+	bool checkInclusion(string s1, string s2) {
+		int n1 = s1.length(), n2 = s2.length();
+		if (n1 > n2) return false;
+		int cnt[26]{};
+		for (char c: s1)++cnt[c - 'a'];
+		for (int i = 0; i < n1; ++i)
+			--cnt[s2[i] - 'a'];
+		if (ok(cnt)) return true;
+		for (int i = n1; i < n2; ++i) {
+			--cnt[s2[i] - 'a'];
+			++cnt[s2[i - n1] - 'a'];
+			if (ok(cnt)) return true;
+		}
+		return false;
+	}
+};