diff --git a/Week 1/ReverseString.cpp b/Week 1/ReverseString.cpp
new file mode 100644
index 0000000..6a7dc04
--- /dev/null
+++ b/Week 1/ReverseString.cpp	
@@ -0,0 +1,20 @@
+/*
+Write a function that reverses a string. The input string is given as an array of characters char[].
+Do not allocate extra space for another array, you must do this by modifying the input array in-place with O(1) extra memory.
+You may assume all the characters consist of printable ascii characters.
+
+Example 1:
+Input: ["h","e","l","l","o"]
+Output: ["o","l","l","e","h"]
+*/
+class Solution {
+public:
+ void reverseString(vector<char>& s) {
+  int start=0,end=s.size()-1;
+  while(start<end){
+    swap(s[start],s[end]);
+    start++;
+    end--;
+  }
+}
+};