add: 220610 [cpp]

cpp/2206/220610.cpp

@@ -0,0 +1,43 @@
+#include <unordered_set>
+#include <string>
+
+/**
+ * 3. Longest Substring Without Repeating Characters
+ * Given a string s, find the length of the longest substring without repeating characters.
+ *
+ * 100% same algorithm as -> 220612.cpp
+ */
+
+class Solution {
+public:
+	static int lengthOfLongestSubstring(const std::string& str) {
+		std::unordered_set<int> s;
+		const int n = str.length();
+		int sum = 0, ret = 0;
+		for (int i = 0, l = 0; i < n; ++i) {
+			std::printf("In loop, i = %d, l = %d\nStart inserting: ", i, l);
+			for (; i < n && !s.count(str[i]); ++i) {
+				++sum; // sum += str[i];
+				s.insert(str[i]);
+				std::printf("%d ", str[i]);
+			}
+			ret = std::max(ret, sum);
+
+			if (i == n)
+				break;
+
+			std::printf("\nEnd inserting at position %d, str[i] = %d, updating ret <- %d\nStart popping: ", i, str[i], ret);
+
+			// pop until reach str[i]
+			for (; str[l] != str[i]; ++l) {
+				s.erase(str[l]);
+				--sum; // sum -= str[l];
+				std::printf("%d ", str[l]);
+			}
+			++l; // where str[l] == str[i]
+			std::printf("\nEnd loop, where i = %d, l = %d\n\n", i, l);
+		}
+
+		return ret;
+	}
+};

cpp/2206/CMakeLists.txt

@@ -3,4 +3,4 @@ PROJECT(2206)
 
 SET(CMAKE_CXX_STANDARD 23)
 
-ADD_EXECUTABLE(2206 220611.cpp)
+ADD_EXECUTABLE(2206 220610.cpp)