#Swapping two variables #Method 1 (using temporary variable) def swap(a,b) temp = a a = b b = temp return a,b end #Method 2 (Ruby magic) def swap(a,b) a,b=b,a return a,b end #Method 3 (Using sum and difference, no temporary variable required) #Caveat: Can lead to integer overflow if a and b are really large integers def swap(a,b) a = a+b b = a-b a = a-b return a,b end #Method 4 (Using bitwise XOR ,no temporary variable required) def swap(a,b) a = a^b b = a^b a = a^b return a,b end