CF498C Array and Operations

You have written on a piece of paper an array of $ n $ positive integers $ a[1],a[2],...,a[n] $ and $ m $ good pairs of integers $ (i_{1},j_{1}),(i_{2},j_{2}),...,(i_{m},j_{m}) $ . Each good pair $ (i_{k},j_{k}) $ meets the following conditions: $ i_{k}+j_{k} $ is an odd number and $ 1

The first line contains two space-separated integers $ n $ , $ m $ ( $ 2

Output the answer for the problem.