2899: Inna and Binary Logic
Time Limit: 2 Sec Memory Limit: 256 MBSubmit: 0 Solved: 0
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Description
Inna is fed up with jokes about female logic. So she started using binary logic instead.
Inna has an array of n elements a1[1],a1[2],...,a1[n]. Girl likes to train in her binary logic, so she does an exercise consisting of n stages: on the first stage Inna writes out all numbers from array a1, on the i-th (i≥2) stage girl writes all elements of array ai, which consists of n-i+1 integers; the k-th integer of array ai is defined as follows: ai[k]=ai-1[k]ANDai-1[k+1]. Here AND is bit-wise binary logical operation.
Dima decided to check Inna's skill. He asks Inna to change array, perform the exercise and say the sum of all 
elements she wrote out during the current exercise.
Help Inna to answer the questions!
The first line contains two integers n and m (1≤n,m≤105) − size of array a1 and number of Dima's questions. Next line contains n integers a1[1],a1[2],...,a1[n] (0≤ai≤105) − initial array elements.
Each of next m lines contains two integers − Dima's question description. Each question consists of two integers pi,vi (1≤pi≤n;0≤vi≤105). For this question Inna should make a1[pi] equals vi, and then perform the exercise. Please, note that changes are saved from question to question.
For each question print Inna's answer on a single line.
3 4
1 1 1
1 1
2 2
3 2
1 2
6
4
7
12