Problem2899--Inna and Binary Logic

2899: Inna and Binary Logic

Time Limit: 2 Sec  Memory Limit: 256 MB
Submit: 0  Solved: 0
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Description

time limit per test
3 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output

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!

Input

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≤pin;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.

Output

For each question print Inna's answer on a single line.

Examples
Input
3 4
1 1 1
1 1
2 2
3 2
1 2
Output
6
4
7
12

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