Tunnels

input/code.cpp: In function 'int main()':
input/code.cpp:20:11: warning: unused variable 'c2' [-Wunused-variable]
     ll c1,c2,c3,c4,c5;
           ^
input/code.cpp:20:14: warning: unused variable 'c3' [-Wunused-variable]
     ll c1,c2,c3,c4,c5;
              ^
input/code.cpp:20:17: warning: unused variable 'c4' [-Wunused-variable]
     ll c1,c2,c3,c4,c5;
                 ^
input/code.cpp:20:20: warning: unused variable 'c5' [-Wunused-variable]
     ll c1,c2,c3,c4,c5;
                    ^
input/code.cpp:21:13: warning: unused variable 'c' [-Wunused-variable]
     int a,b,c;
             ^

#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

ll mod = 1000000007ll;
ll n,m,k,x,y;


vector<vector<ll> > C(100001 , vector<ll>());
ll deg[100001] = {0};
ll indeg[100001] = {0};
vector<ll> L;

int main()
{
    //freopen("input.txt","r",stdin);
    //freopen("output.txt","w",stdout);

    ll c1,c2,c3,c4,c5;
    int a,b,c;

    cin >>n  >> m;

    for(c1 = 0; c1 < n; c1++){
        L.push_back(0);
    }

    for(c1 = 0; c1 < m; c1++){
        cin >> a >> b;
        a--;
        b--;
        deg[a]++;
        indeg[b]++;
        C[a].push_back(b);
    }

    ll ans = 0;

    for(c1 = 0; c1 < n; c1++){
        ans += max(0ll , deg[c1] - indeg[c1]);
    }
    cout << ans << "\n";

    return 0;
}

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 1

Verdict: ACCEPTED

Test 3

Group: 1

Verdict: ACCEPTED

Test 4

Group: 1

Verdict: ACCEPTED

Test 5

Group: 1

Verdict: ACCEPTED

Test 6

Group: 2

Verdict: ACCEPTED

Test 7

Group: 2

Verdict: ACCEPTED

Test 8

Group: 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: ACCEPTED

Test 10

Group: 2

Verdict: ACCEPTED

Test 11

Group: 3

Verdict: ACCEPTED

Test 12

Group: 3

Verdict: ACCEPTED

Test 13

Group: 3

Verdict: ACCEPTED

Test 14

Group: 3

Verdict: ACCEPTED

Test 15

Group: 3

Verdict: ACCEPTED