Getting WA in RPLD

[vibvibgyor]

Please help me out, below is the code.. I am trying from last 5 days

#include<iostream>
#include<map>
using namespace std;
int main()
{
    map<long long, long long> v;
    int lo;
    long long t,n,r,i,c,z,temp;
    cin>>t;
    temp = 1;
    while(t--)
    {
        lo = 0;
        cin>>n>>r;
        for(z=1;z<=r;z++)
        {
            cin>>i>>c;
            if(v[i] == c)
            lo = 1;
        else
        {
            v[i] = c;
        }
    }
    if(lo == 0)
        cout<<"Scenario #"<<temp<<": possible\n";
    else
        cout<<"Scenario #"<<temp<<": impossible\n";
    temp++;
}
return 0;
}

[leppyr64]

if one student sees the same subject two or more times

Not necessarily in order.

[vibvibgyor]

Hello Sir thanks a lot for replying. But my program fulfills the criteria as mentioned by you? Please elaborate. I am very much confused.

[leppyr64]

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