#include<cstdio>
#include<set>
const int N=1e5+6;
typedef long long LL;
int n,a[N];
struct BIT{LL b[N];inline void add(int i,int x){for(;i<N;i+=i&-i)b[i]+=x;}inline LL ask(int i){LL x=0;for(;i;i^=i&-i)x+=b[i];return x;}
}odd,even;
std::set<int>s;
LL ans=0;
LL get(int x){if(x<1||x>n)return 0;auto it=s.find(x);if(*it==1){auto nxt=it;++nxt;if(a[*it]<a[*nxt]){if(*nxt&1)return odd.ask(*nxt-1)-odd.ask(*it-1);elsereturn even.ask(*nxt-1)-even.ask(*it-1);}else return 0;}if(*it==n){auto pre=it;--pre;if(a[*pre]>=a[*it]){if(*pre&1)return odd.ask(*it)-odd.ask(*pre-1);elsereturn even.ask(*it)-even.ask(*pre-1);}else return a[n];}auto pre=it,nxt=it;--pre,++nxt;if(a[*pre]>=a[*it]&&a[*it]<a[*nxt]){LL ret=0;if(*pre&1)ret+=odd.ask(*it-1)-odd.ask(*pre-1);elseret+=even.ask(*it-1)-even.ask(*pre-1);if(*nxt&1)ret+=odd.ask(*nxt-1)-odd.ask(*it);elseret+=even.ask(*nxt-1)-even.ask(*it);if((*pre&1)==(*it&1)&&(*nxt&1)==(*it&1))ret+=a[*it];return ret;}else return 0;
}
int main(){scanf("%d",&n);for(int i=1;i<=n;++i)scanf("%d",a+i),((i&1)?odd:even).add(i,a[i]);s.insert(-2),s.insert(-1),s.insert(n+2),s.insert(n+3);s.insert(1);for(int i=2;i<n;++i)if(a[i-1]<a[i]&&a[i]>=a[i+1]||a[i-1]>=a[i]&&a[i]<a[i+1])s.insert(i);s.insert(n);for(int i:s)ans+=get(i);int q;for(scanf("%d",&q);q--;){int x,y;scanf("%d%d",&x,&y);int nxt=*s.upper_bound(x),pre=*--s.lower_bound(x);ans-=get(nxt),ans-=get(pre);nxt=*s.upper_bound(nxt),pre=*--s.lower_bound(pre);ans-=get(nxt),ans-=get(pre);if(s.count(x))ans-=get(x),s.erase(x);s.erase(x-1),s.erase(x+1);if(x&1)odd.add(x,-a[x]),odd.add(x,y);elseeven.add(x,-a[x]),even.add(x,y);a[x]=y; for(int i=x-1;i<=x+1;++i){if(i<1||i>n)continue;if(i==1||i==n)s.insert(i);elseif(a[i-1]<a[i]&&a[i]>=a[i+1]||a[i-1]>=a[i]&&a[i]<a[i+1])s.insert(i);}for(auto l=s.find(pre),r=s.upper_bound(nxt);l!=r;++l)ans+=get(*l);printf("%lld\n",ans);}return 0;
}