Added day3

Author: coderjojo

leetcode/day3.cpp

@@ -0,0 +1,17 @@
+class Solution {
+  public:
+    int maxSubArray(vector<int>& nums) {
+            
+            int ans = INT_MIN, t = 0;
+            
+            for(int x : nums){
+                        t+= x;
+                        ans = max(ans,t);
+                        
+                        t= max(t,0);
+                    }
+            
+            return ans;
+            
+        }
+};