#include<iostream>
#include<cstdio>
#define N 200000
using namespace std;
int read()
{
    char c=0;
    int sum=0,f=1;
    while (c!='-'&&(c<'0'||c>'9')) c=getchar();
    if (c=='-') c=getchar(),f=-1;
    while ('0'<=c&&c<='9') sum=sum*10+c-'0',c=getchar();
    return sum*f;
}
struct seg
{
    struct node
    {
	int l,r;
	long long minn,lazy;
    };
    node tree[(N<<2)+1];
    void push_up(int k)
    {
	tree[k].minn=min(tree[k<<1].minn,tree[k<<1|1].minn);
	return;
    }
    void spread(int k)
    {
	if (tree[k].lazy)
	{
	    tree[k<<1].minn+=tree[k].lazy,tree[k<<1].lazy+=tree[k].lazy;
	    tree[k<<1|1].minn+=tree[k].lazy,tree[k<<1|1].lazy+=tree[k].lazy;
	    tree[k].lazy=0;
	}
	return;    
    }
    void build(int k,int l,int r)
    {
	tree[k].l=l,tree[k].r=r;
	if (l==r) return;
	int mid=(l+r)>>1;
	build(k<<1,l,mid),build(k<<1|1,mid+1,r);
	return;
    }
    void add(int k,int l,int r,int d)
    {
	if (tree[k].l==l&&tree[k].r==r)
	{
	    tree[k].minn+=d,tree[k].lazy+=d;
	    return;
	}
	spread(k);
	int mid=(tree[k].l+tree[k].r)>>1;
	if (r<=mid) add(k<<1,l,r,d);
	else if (l>=mid+1) add(k<<1|1,l,r,d);
	else add(k<<1,l,mid,d),add(k<<1|1,mid+1,r,d);
	push_up(k);
	return;
    }
};
seg T;
int n,q,c[N+1];
long long res,resA,resB;
int main()
{
    int x;
    long long d;
    n=read(),q=read(),T.build(1,0,n);
    for (int i=1;i<=n;++i)
    {
	c[i]=read();
	if (c[i]&1) resA++,T.add(1,(i+2)>>1,n,1);
	resB+=(c[i]>>1),T.add(1,i,n,-(c[i]>>1));
    }
    while (q--)
    {
	x=read(),d=read();
	if (c[x]&1) resA--,T.add(1,(x+2)>>1,n,-1);
	resB-=(c[x]>>1),T.add(1,x,n,c[x]>>1);
	c[x]+=d;
	if (c[x]&1) resA++,T.add(1,(x+2)>>1,n,1);
	resB+=(c[x]>>1),T.add(1,x,n,-(c[x]>>1));
	d=resA+resB+(T.tree[1].minn<<1);
	printf("%lld\n",d+((resB-d)<<1)/3);
    }
    return 0;
}