Hi can someone help me with this

#include <bits/stdc++.h>
using namespace std;
#define ll long long
multiset<int> s;
int a[1000000], p[1000000];
ll num[1000000];
ll ans[1000000];
void add(int x,int y){
	if(num[x])s.erase(s.find(num[x]));
	num[x]+=y;
	if(num[x])s.insert(num[x]);
}

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    ll test;
    cin>>test;
    while(test--)
    {
        ll n,k,q;
        cin>>n>>k>>q;
        for(int i = 1; i <= n; i++){
            cin>>a[i];
            a[i] -= i; a[i] += n;
        }
        memset(num,0,9*n);
        s = {};
        for(int i = 1; i <= n; i++){
            if(i>k) add(a[i-k],-1);
            add(a[i],1);
            if(i>=k) ans[i-k+1] = k - *s.rbegin();
        }
        while(q--){
            ll l,r;
            cin>>l>>r;
            cout<<ans[l]<<endl;
        }
    }
    return 0;
}

Running the code for problem, test case 2 shows TLE but if I change the line 7 to int num[1000000] then it passes.