003 solved.

liuyubobobo · liuyubobobo · commit 381fc9b9a9d4 · 2017-10-21T18:06:20.000-07:00
diff --git a/0003-Longest-Substring-Without-Repeating-Characters/cpp-0003/CMakeLists.txt b/0003-Longest-Substring-Without-Repeating-Characters/cpp-0003/CMakeLists.txt
@@ -0,0 +1,7 @@
+cmake_minimum_required(VERSION 3.5)
+project(cpp_0003)
+
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
+
+set(SOURCE_FILES main.cpp)
+add_executable(cpp_0003 ${SOURCE_FILES})
diff --git a/0003-Longest-Substring-Without-Repeating-Characters/cpp-0003/main.cpp b/0003-Longest-Substring-Without-Repeating-Characters/cpp-0003/main.cpp
@@ -0,0 +1,43 @@
+/// Source : https://leetcode.com/problems/longest-substring-without-repeating-characters/description/
+/// Author : liuyubobobo
+/// Time   : 2017-07-12
+
+#include <iostream>
+
+using namespace std;
+
+/// Using Sliding Window
+/// Time Complexity: O(len(s))
+/// Space Complexity: O(len(charset))
+class Solution {
+public:
+    int lengthOfLongestSubstring(string s) {
+
+        int freq[256] = {0};
+
+        int l = 0, r = -1; //sliding window: s[l...r]
+        int res = 0;
+
+        while( r + 1 < s.size() ){
+
+            if( freq[s[r+1]] == 0 )
+                freq[s[++r]] ++;
+            else    //freq[s[r+1]] == 1
+                freq[s[l++]] --;
+
+            res = max( res , r-l+1);
+        }
+
+        return res;
+    }
+};
+
+int main() {
+
+    cout << Solution().lengthOfLongestSubstring( "abcabcbb" )<<endl;
+    cout << Solution().lengthOfLongestSubstring( "bbbbb" )<<endl;
+    cout << Solution().lengthOfLongestSubstring( "pwwkew" )<<endl;
+    cout << Solution().lengthOfLongestSubstring( "" )<<endl;
+
+    return 0;
+}
diff --git a/0003-Longest-Substring-Without-Repeating-Characters/java-0003/src/Solution.java b/0003-Longest-Substring-Without-Repeating-Characters/java-0003/src/Solution.java
@@ -0,0 +1,35 @@
+/// Source : https://leetcode.com/problems/longest-substring-without-repeating-characters/description/
+/// Author : liuyubobobo
+/// Time   : 2017-10-21
+
+/// Using Sliding Window
+/// Time Complexity: O(len(s))
+/// Space Complexity: O(len(charset))
+public class Solution {
+    public int lengthOfLongestSubstring(String s) {
+
+        int[] freq = new int[256];
+
+        int l = 0, r = -1; //sliding window: s[l...r]
+        int res = 0;
+
+        while( r + 1 < s.length() ){
+
+            if( r + 1 < s.length() && freq[s.charAt(r+1)] == 0 )
+                freq[s.charAt(++r)] ++;
+            else    //freq[s[r+1]] == 1
+                freq[s.charAt(l++)] --;
+
+            res = Math.max( res , r-l+1);
+        }
+
+        return res;
+    }
+
+    public static void main(String[] args) {
+        System.out.println((new Solution()).lengthOfLongestSubstring( "abcabcbb" ));
+        System.out.println((new Solution()).lengthOfLongestSubstring( "bbbbb" ));
+        System.out.println((new Solution()).lengthOfLongestSubstring( "pwwkew" ));
+        System.out.println((new Solution()).lengthOfLongestSubstring( "" ));
+    }
+}
diff --git a/readme.md b/readme.md
@@ -30,6 +30,8 @@ email: [liuyubobobo@gmail.com](mailto:liuyubobobo@gmail.com)
 
 | ID | Problem | C++ | Java |
 | --- | --- | :---: | :---: |
+| 003 | [Longest-Substring-Without-Repeating-Characters](https://leetcode.com/problems/longest-substring-without-repeating-characters/description/) | [C++](0003-Longest-Substring-Without-Repeating-Characters/cpp-0003/) | [Java](Longest-Substring-Without-Repeating-Characters/java-0003/src/) |
+| | | | |
 | 079 | [Word Search](https://leetcode.com/problems/word-search/description/) | [C++](0079-Word-Search/cpp-0079/) | [Java](0079-Word-Search/java-0079/src/) |
 | | | | |
 | 283 | [Move Zeroes](https://leetcode.com/problems/move-zeroes/) | [C++](0283-Move-Zeroes/cpp-0283/) | [Java](0283-Move-Zeroes/java-0283/src/) |
