Ping

input/code.cpp: In function 'int main()':
input/code.cpp:65:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d%d",&n,&q,&p);
                             ^
input/code.cpp:70:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d%d",&u,&v,&d);
                                 ^

#include <cstdio>
#include <queue>
#include <algorithm>
#include <vector>
#include <set>

#define all(x) (x).begin(),x.end()

#define pb push_back
#define mp make_pair
#define x1 first
#define x2 second.first
#define x3 second.second
#define trip(a,b,c) mp(a,mp(b,c))

using namespace std;
const int inf = 1000000007;

    int n,q,p;
vector<vector<pair<int,pair<int,int> > > > G;

bool test(int thr)
{
    set<pair<int,int> > pq;

    int target = n-1;
    vector<int> dist(n,inf);
    vector<bool> done(n,false);
    dist[0]=0;
    pq.insert(mp(0,0));

    while(!pq.empty())
    {
        pair<int,int> X = *pq.begin();
        pq.erase(pq.begin());
        int u = X.second;
        int d = X.first;
        if(d > p)
            return false;
        if(u == target)
            return true;
        if(done[u])
            continue;
        done[u]=true;
        for(auto& it : G[u])
        {
            if(it.x3 >= thr)
                continue;
            int v = it.x1;
            int vd = dist[u]+it.x2;
            if(vd>p)
                continue;
            if(vd<dist[v])
            {
                dist[v]=vd;
                pq.insert(mp(vd,v));
            }
        }
    }
    return false;
}

int main()
{
    scanf("%d%d%d",&n,&q,&p);
    G.resize(n);
    for(int i=0;i<q;i++)
    {
        int u,v,d;
        scanf("%d%d%d",&u,&v,&d);
        u--;
        v--;
        G[u].pb(trip(v,d,i));
        G[v].pb(trip(u,d,i));
    }

    int low = 0;
    int high = q;

    if(!test(q))
    {
        puts("QAQ");
        return 0;
    }
    while(high>low+1)
    {
        int mid = low + (high-low)/2;
        if(test(mid))
            high = mid;
        else
            low = mid;
    }
    printf("%d\n",high);
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED