#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ld long double
#define ull unsigned long long
#define pll pair<ll, ll>
#define ppll pair< pair<long long, long long>, long long >
#define ff first
#define ss second
#define pb push_back
#define pf push_front
const ll DIM = 800 + 7;
const ll INF = 1e18;
const ll mod = 998244353;
const ll maxlog = 20;
const ll bsize = 350;
ll d[DIM], c[DIM], nxt[DIM];
bool flag[DIM];
vector<ll> s[DIM], v[DIM];
ll path[DIM], pos[DIM];
void solve() {
ll n, nq;
cin >> n >> nq;
for (int i=1; i<=n; i++) {
cin >> d[i] >> c[i];
nxt[i] = 0;
flag[i] = 1;
}
c[0] = INF;
stack<ll> st;
for (int i=1; i<=n; i++) {
while (!st.empty() && d[st.top()] < d[i]) {
nxt[st.top()] = i;
flag[i] = 0;
st.pop();
}
st.push(i);
}
ll cnt = 0;
for (int i=1; i<=n; i++) {
if (!flag[i]) continue;
cnt++;
ll cur = i, sum = 0;
s[cnt].pb(0);
v[cnt].pb(-1);
do {
sum += c[cur];
s[cnt].pb(sum);
v[cnt].pb(cur);
path[cur] = cnt; pos[cur] = s[cnt].size() - 1;
cur = nxt[cur];
} while (cur != 0);
}
for (int i=1; i<=cnt; i++) {
v[i].pb(0);
s[i].pb(s[i][s[i].size()-1] + c[0]);
}
for (int i=1; i<=nq; i++) {
ll r, vol;
cin >> r >> vol;
ll need = s[path[r]][pos[r]-1] + vol;
ll it = lower_bound(s[path[r]].begin(), s[path[r]].end(), need) - s[path[r]].begin();
cout << v[path[r]][it] << endl;
}
}
int main() {
ios::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
//freopen("atlarge.in", "r", stdin);
//freopen("atlarge.out", "w", stdout);
int ntest = 1;
//cin >> ntest;
while (ntest--) {
solve();
}
return 0;
}
;
