415. Add Strings

Author: amitbansal7

add-strings.cpp

@@ -0,0 +1,23 @@
+//Runtime: 12 ms
+class Solution {
+public:
+	string addStrings(string num1, string num2) {
+		int i = num1.size() - 1;
+		int j = num2.size() - 1;
+		int carry = 0;
+		string res;
+		while (i >= 0 || j >= 0) {
+			int x = (i >= 0 ? num1[i] - '0' : 0) + (j >= 0 ? num2[j] - '0' : 0) + carry;
+			carry = x / 10;
+			res += (x % 10 + '0');
+			i--; j--;
+		}
+
+		if (carry != 0) {
+			res += (carry + '0');
+		}
+
+		reverse(res.begin(), res.end());
+		return res;
+	}
+};