Time: 3 ms (63.04%) | Memory: 10.1 MB (33.77%) - LeetSync

Author: kaleaditya779

415-add-strings/add-strings.cpp

@@ -0,0 +1,61 @@
+class Solution {
+public:
+    string addStrings(string num1, string num2) {
+        int n1 = num1.size();
+        int n2 = num2.size();
+        string re;
+        unordered_map<int, char> intChar = {
+            {1, '1'}, {2, '2'}, {3, '3'}, {4, '4'}, {5, '5'}, {6, '6'}, {7, '7'}, {8, '8'}, {9, '9'}, {0, '0'}
+        };
+
+        if (n1 >= n2){
+            int diff = n1-n2;
+            string di;
+            for(int i=1; i<=diff; i++){
+                di.push_back('0');
+            }
+            num2 = di+num2;
+            cout<<num2;
+            int carry=0;
+            for (int i=n1-1; i>=0; i--){
+                int r = num1[i]-'0';
+                r += (num2[i]-'0') + carry;
+                if (r<=9){
+                    carry=0;
+                    re.push_back(intChar[r]);
+                } else {
+                    carry=1;
+                    r = r-10;
+                    re.push_back(intChar[r]);
+                }
+            }
+            if (carry==1) re.push_back('1');
+            reverse(re.begin(), re.end());
+            return re;
+        } else {
+            int diff = n2-n1;
+            string di;
+            for(int i=1; i<=diff; i++){
+                di.push_back('0');
+            }
+            num1 = di+num1;
+            cout<<num1;
+            int carry=0;
+            for (int i=n2-1; i>=0; i--){
+                int r = num1[i]-'0';
+                r += (num2[i]-'0') + carry;
+                if (r<=9){
+                    carry=0;
+                    re.push_back(intChar[r]);
+                } else {
+                    carry=1;
+                    r = r-10;
+                    re.push_back(intChar[r]);
+                }
+            }
+            if (carry==1) re.push_back('1');
+            reverse(re.begin(), re.end());
+            return re;
+        }
+    }
+};