/* Ajay Jadhav */
#include <iostream>
#include <cstdio>
#include <algorithm>
#include <deque>
#include <vector>
#include <cstdlib>
#include <iomanip>
#include <cmath>
#include <queue>
#include <map>
#include <set>
#include <stack>
#include <ctime>
#include <string.h>
#include <climits>
#include <cstring>
using namespace std;
#define ll long long
#define pb push_back
#define pii pair<int,int>
#define vi vector<int>
#define vii vector<pii>
#define mi map<int,int>
#define mii map<pii,int>
#define all(a) (a).begin(),(a).end()
#define x first
#define y second
#define sz(x) (int)x.size()
#define hell 1000000007
#define rep(i,a,b) for(int i=a;i<b;i++)
#define endl '\n'
vector<int> reverse(vector<int> a)
{
int n = sz(a);
rep (i, 0, n / 2)
{
swap(a[i], a[n - i]);
}
return a;
}
Compilation message
/usr/bin/ld: /tmp/ccvObr8t.o: in function `main':
grader.cpp:(.text.startup+0x17d): undefined reference to `reverse(std::vector<long long, std::allocator<long long> >)'
collect2: error: ld returned 1 exit status
