Help me in solving PREP68 problem

help
,
1

My issue

Runtime Error

My code

#include <bits/stdc++.h>
using namespace std;

bool checkdiff(vector<int>&v,int size, int target)
{
    sort(v.begin(),v.end());
    int i=0,j=1;
    while(i<j)
    {
        if(abs(v[i]-v[j])==target)
        return true;
        else if((v[j]-v[i]<target))
        {
            j++;
        }
        else{
            i++;
        }
    }
    return 0;
}

int main() {

int t; cin>>t;
while(t--)
{
    int size; cin>>size;
    int target; cin>>target;
    vector<int> v;
    for(int i=0;i<size;i++)
    {
        int x;
        cin>>x;
        v.push_back(x);
    }
   int ans=checkdiff(v,size,target);
   cout<<ans<<endl;
}
	return 0;
}

Learning course: Two pointers
Problem Link: CodeChef: Practical coding for everyone