G. Mysterious numbers - 2time limit per test2 secondsmemory limit per test256 megabytesinputstandard inputoutputstandard outputInputThe only line of input contains three integers a1, a2, a3 (1 ≤ a1, a2, a3 ≤ 20), separated by spaces.OutputOutput a single integer.ExamplesInput2 3 2Output5Input13 14 1Output14Input14 5 9Output464Input17 18 3Output53 
Input2 3 2
Output5
['*special problem', '*1600']