add: descriptions

2202/220202-CN.cpp

@@ -1,6 +1,13 @@
 #include <string>
 #include <iostream>
 
+/**
+ * 2000. Reverse Prefix of Word
+ * Given a 0-indexed string word and a character ch, reverse the segment of word that starts at index 0 and ends at the index of the first occurrence of ch (inclusive). If the character ch does not exist in word, do nothing.
+ * For example, if word = "abcdefd" and ch = "d", then you should reverse the segment that starts at 0 and ends at 3 (inclusive). The resulting string will be "dcbaefd".
+ * Return the resulting string.
+ */
+
 class Solution {
 public:
 	static std::string reversePrefix(std::string word, char ch) {

2202/220202.cpp

@@ -1,6 +1,12 @@
 #include <vector>
 #include <string>
 
+/**
+ * 438. Find All Anagrams in a String
+ * Given two strings s and p, return an array of all the start indices of p's anagrams in s. You may return the answer in any order.
+ * An Anagram is a word or phrase formed by rearranging the letters of a different word or phrase, typically using all the original letters exactly once.
+ */
+
 class Solution {
 private:
 	template<int N>

2202/220203-CN.cpp

@@ -4,6 +4,18 @@
 #include <cstdint>
 #include <algorithm>
 
+/**
+ * 1414. Find the Minimum Number of Fibonacci Numbers Whose Sum Is K
+ * Given an integer k, return the minimum number of Fibonacci numbers whose sum is equal to k. The same Fibonacci number can be used multiple times.
+ *
+ * The Fibonacci numbers are defined as:
+ *
+ * F[1] = 1
+ * F[2] = 1
+ * F[n] = F[n-1] + F[n-2] for n > 2.
+ * It is guaranteed that for the given constraints we can always find such Fibonacci numbers that sum up to k.
+ */
+
 class Solution {
 private:
 	inline static constexpr int fib[] = {1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, 2584, 4181, 6765, 10946, 17711, 28657, 46368, 75025, 121393, 196418, 317811, 514229, 832040, 1346269, 2178309, 3524578, 5702887, 9227465, 14930352, 24157817, 39088169, 63245986, 102334155, 165580141, 267914296, 433494437, 701408733, 1134903170, 1836311903};

2202/220203.cpp

@@ -2,6 +2,13 @@
 #include <cstdio>
 #include <unordered_map>
 
+/**
+ * 454. 4Sum II
+ * Given four integer arrays nums1, nums2, nums3, and nums4 all of length n, return the number of tuples (i, j, k, l) such that:
+ * 0 <= i, j, k, l < n
+ * nums1[i] + nums2[j] + nums3[k] + nums4[l] == 0
+ */
+
 class Solution {
 public:
 	static int fourSumCount(const std::vector<int>& nums1, const std::vector<int>& nums2, const std::vector<int>& nums3, const std::vector<int>& nums4) {