#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define vl vector<ll>
#define vs vector<string>
#define vb vector<bool>
#define ull unsigned long long
#define pll pair<ll, ll>
#define pb push_back
#define fi first
#define se second
#define ff(i, p, x) for (ll i = p; i < x; i++)
#define all(a) (a).begin(), (a).end()
#define rall(a) (a).rbegin(), (a).rend()
#define ed "\n"
#define IO std::ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
ll MOD = 1e9+7;
ll besthub(ll r, ll l, vl x, ll b){
vl psum(r+1, 0);
ff(i, 1, r){
psum[i] = psum[i-1]+x[i];
}
ll ri = 0, c = 0;
ff(le, 0, r){
while(ri < r){
ll mid = le + (ri-le)/2;
if(le % 2 == ri % 2){
mid++;
}
ll q = 0;
if((le+ri+1) % 2 != 0){
q -= x[mid];
}
q -= psum[mid]-psum[le];
q += psum[ri+1] - psum[mid];
if(q > b){
break;
}
ri++;
}
if(c < ri-le){
c = ri-le;
}
if(ri == r){
break;
}
}
return c;
}
/*
int main(){
IO
ll r, l, b;
cin >> r >> l >> b;
vl x(r);
ff(i, 0, r){
cin >> x[i];
}
cout << besthub(r, l, x, b);
return 0;
}
*/
Compilation message
/usr/bin/ld: /tmp/ccG755cW.o: in function `main':
grader.cpp:(.text.startup+0xae): undefined reference to `besthub(int, int, int*, long long)'
collect2: error: ld returned 1 exit status