new snippet - swap numbers

snippets/cpp/math-and-numbers/swap-numbers.md

@@ -0,0 +1,19 @@
+---
+title: Swap numbers
+description: Swaps two numbers without using third variable
+author: Emosans
+tags: swap,numbers
+---
+
+```cpp
+#include<tuple>
+std::tuple<int,int> swap(int num1,int num2){
+    num1=num1+num2;
+    num2=num1-num2;
+    num1=num1-num2;
+    return std::make_tuple(num1,num2);
+}
+
+// Usage
+auto swapped=swap(3,4); // Returns a tuple (access the values using std::get<0>(swapped)/std::get<1>(swapped))
+```