#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll,ll> P;
typedef vector<ll> vi;
typedef vector<vi> vvi;
#define rep(i,n) for(ll i=0;i<(ll)(n);i++)
#define REP(i,k,n) for(ll i=(ll)(k);i<(ll)(n);i++)
#define all(a) a.begin(),a.end()
#define pb emplace_back
template<class T> void out(T a){cout<<a<<'\n';}
bool check(ll n,vi v,ll k){
    vi pairs(n),singles(n);
    ll cnt=k;
    for(int i=n-1;i>=0;i--){
        pairs[i]=min(cnt,v[i]/2);
        cnt-=pairs[i];
    }
    if(cnt>0)return false;
    rep(i,n)singles[i]=v[i]-pairs[i]*2;
    ll l=0;
    rep(i,n){
        while(pairs[i]>0){
            while(l<n&&singles[l]==0)l++;
            if(l==n)return false;
            if((l+1)>=(i+1)*2)return false;
            ll tmp=min(pairs[i],singles[l]);
            pairs[i]-=tmp;singles[l]-=tmp;
        }
    }
    return true;
}
vi sol_naive(ll n,ll q,vi v,vvi query){
    vi ans;
    rep(qq,q){
        v[query[qq][0]-1]+=query[qq][1];
        ll sum=0;for(ll x:v)sum+=x;
        ll ok=0,ng=sum/3+1;
        while(ng-ok>1){
            ll md=(ok+ng)/2;
            if(check(n,v,md))ok=md;
            else ng=md;
        }
        ans.pb(ok);
    }
    return ans;
}
int main(){
    ll n,q;cin>>n>>q;
    vi v(n);rep(i,n)cin>>v[i];
    vvi query(q,vi(2));
    rep(i,q)rep(j,2)cin>>query[i][j];
    vi res=sol_naive(n,q,v,query);
    for(ll x:res)out(x);
}