#include <bits/stdc++.h>
using namespace std;
#define int long long
#define endl "\n"
const int MOD = 1e9 + 7;
pair<int,int> a[10000000];
signed main(){
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
int n,q;
cin >> n>>q;
int pref[n+1]={0};
for(int i=0;i<n;i++){
cin >> a[i].first>>a[i].second;
pref[i+1]=a[i].second;
pref[i+1]+=pref[i];
}
pref[n]=a[n-1].second;
pref[n]+=pref[n-1];
a[n]={INT_MAX,INT_MAX};
if(n<=1000&&q<=2000){
while(q--){
int r,v;
cin >>r >> v;
int cur=a[r-1].first;
v-=a[r-1].second;
int ans=r-1;
for(int i=r;i<=n;i++){
if(a[i].first>cur){
if(v<=0) {
break;
}
ans=i;
cur=a[i].first;
v-=a[i].second;
}
}
if(ans==n)ans=-1;
cout<<ans+1<<endl;
}
}
else{
while(q--){
int r,v;
cin >>r >> v;
v+=pref[r-1];
int ans=lower_bound(pref,pref+n,v)-pref;
if(v>pref[ans+1])ans++;
if(ans==n)ans=0;
cout<<ans<<endl;
}
}
}
