Problem:


Score : 500 points

Problem Statement

There are N towns numbered 1 to N and M roads. The i-th road connects Town A_i and Town B_i bidirectionally and has a length of C_i.

Takahashi will travel between these towns by car, passing through these roads. The fuel tank of his car can contain at most L liters of fuel, and one liter of fuel is consumed for each unit distance traveled. When visiting a town while traveling, he can full the tank (or choose not to do so). Travel that results in the tank becoming empty halfway on the road cannot be done.

Process the following Q queries:

The tank is now full. Find the minimum number of times he needs to full his tank while traveling from Town s_i to Town t_i. If Town t_i is unreachable, print -1.

Constraints

All values in input are integers.

2 \leq N \leq 300

0 \leq M \leq \frac{N(N-1)}{2}

1 \leq L \leq 10^9

1 \leq A_i, B_i \leq N

A_i \neq B_i

\left(A_i, B_i\right) \neq \left(A_j, B_j\right) (if i \neq j)

\left(A_i, B_i\right) \neq \left(B_j, A_j\right) (if i \neq j)

1 \leq C_i \leq 10^9

1 \leq Q \leq N\left(N-1\right)

1 \leq s_i, t_i \leq N

s_i \neq t_i

\left(s_i, t_i\right) \neq \left(s_j, t_j\right) (if i \neq j)

Input

Input is given from Standard Input in the following format:

N M L
A_1 B_1 C_1
:
A_M B_M C_M
Q
s_1 t_1
:
s_Q t_Q

Output

Print Q lines.

The i-th line should contain the minimum number of times the tank needs to be fulled while traveling from Town s_i to Town t_i. If Town t_i is unreachable, the line should contain -1 instead.

Sample Input 1

3 2 5
1 2 3
2 3 3
2
3 2
1 3

Sample Output 1

0
1

To travel from Town 3 to Town 2, we can use the second road to reach Town 2 without fueling the tank on the way.

To travel from Town 1 to Town 3, we can first use the first road to get to Town 2, full the tank, and use the second road to reach Town 3.

Sample Input 2

4 0 1
1
2 1

Sample Output 2

-1

There may be no road at all.

Sample Input 3

5 4 4
1 2 2
2 3 2
3 4 3
4 5 2
20
2 1
3 1
4 1
5 1
1 2
3 2
4 2
5 2
1 3
2 3
4 3
5 3
1 4
2 4
3 4
5 4
1 5
2 5
3 5
4 5

Sample Output 3

0
0
1
2
0
0
1
2
0
0
0
1
1
1
0
0
2
2
1
0



Sample input:
3 2 5
1 2 3
2 3 3
2
3 2
1 3


Sample output:
0
1

Submission status: Runtime Error

Solution code:
from scipy.sparse.csgraph import dijkstra
import sys
input = sys.stdin.readline
def solve():
  inf = 0
  n,m,l = (int(i) for i in input().split())
  path = [[-1*inf]*n for _ in range(n)]
  for i in range(m):
    a,b,c = (int(i) for i in input().split())
    path[a-1][b-1] = c
    path[b-1][a-1] = c
  d = dijkstra(path)
  q = int(input())
  minipath = [[-1*inf]*n for _ in range(n)]
  for i in range(n):
    for j in range(n):
      if d[i][j] <= l:
        minipath[i][j] = 1
  d2 = dijkstra(minipath)

  for i in range(q):
    s,t = (int(i) for i in input().split())
    s,t = s-1,t-1
    cost = d2[s][t]
    if cost == inf:
      print(-1)
    else:
      print(int(cost)-1)

solve()

Submission status: Runtime Error

Solution code:
from scipy.sparse.csgraph import dijkstra
import sys
input = sys.stdin.readline
def solve():
  inf = float("Inf")
  n,m,l = (int(i) for i in input().split())
  path = [[-1*inf]*n for _ in range(n)]
  for i in range(m):
    a,b,c = (int(i) for i in input().split())
    path[a-1][b-1] = c
    path[b-1][a-1] = c
  d = dijkstra(path)
  q = int(input())
  minipath = [[-1*inf]*n for _ in range(n)]
  for i in range(n):
    for j in range(n):
      if d[i][j] <= l:
        minipath[i][j] = 1
  d2 = dijkstra(minipath)

  for i in range(q):
    s,t = (int(i) for i in input().split())
    s,t = s-1,t-1
    cost = d2[s][t]
    if cost == inf:
      print(-1)
    else:
      print(int(cost)-1)

solve()

Submission status: Runtime Error

Solution code:
/**
 * code generated by JHelper
 * More info: https://github.com/AlexeyDmitriev/JHelper
 * @author TM
 */


#include <iostream>
#include <algorithm>
#include <vector>
#include <string>
#include <queue>
#include <map>
#include <set>
#include <functional>
#include <cmath>
#include <numeric>
#include <iterator>

#define SIZE 100005
#define MOD 1000000007
#define INF 100000005

using namespace std;

class ETravelByCar {
public:

    void solve(std::istream &cin, std::ostream &cout) {
        long long int n, m, l;
        cin >> n >> m >> l;

        graph.resize(n, vector<long long int>(n, INF));
        for (int i = 0; i < n; ++i) {
            graph[i][i] = 0;
        }
        for (int i = 0; i < m; ++i) {
            long long int a, b, c;
            cin >> a >> b >> c;
            graph[a - 1][b - 1] = c;
            graph[b - 1][a - 1] = c;
        }
        for (int i = 0; i < n; ++i)
            for (int j = 0; j < n; ++j)
                for (int k = 0; k < n; ++k) {
                    graph[j][k] = min(graph[j][k], graph[j][i] + graph[i][k]);
                }


        dist.resize(n, vector<long long int>(n, INF));
        for (int i = 0; i < n; ++i)
            for (int j = 0; j < n; ++j)
                if (graph[i][j] <= l) dist[i][j] = 1;

        for (int i = 0; i < n; ++i)
            for (int j = 0; j < n; ++j)
                for (int k = 0; k < n; ++k) {
                    dist[j][k] = min(dist[j][k], dist[j][i] + dist[i][k]);
                }
//        for (int i1 = 0; i1 < n; ++i1){
//            for (int k1 = 0; k1 < n; ++k1){
//                cout << dist[i1][k1] << " ";
//            }
//            cout << endl;
//        }
        long long int q;
        cin >> q;
        for (int i = 0; i < q; ++i) {
            int s, t;
            cin >> s >> t;
            if (dist[s - 1][t - 1] < INF) {
                cout << dist[s - 1][t - 1] - 1 << endl;
            } else {
                cout << -1 << endl;
            }
        }
    }

    vector<vector<long long int> > graph;
    vector<vector<long long int> > dist;
};


int main() {
    ETravelByCar solver;
    std::istream &in(std::cin);
    std::ostream &out(std::cout);
    solver.solve(in, out);
    return 0;
}

Submission status: Runtime Error

Solution code:
import sys
from scipy.sparse.csgraph import csgraph_from_dense
from scipy.sparse.csgraph import floyd_warshall
input = sys.stdin.readline


n, m, energy = map(int, input().split())
edges = [[float('INF')]*n for _ in range(n)]

for i in range(m):
    a, b, c = map(int, input().split())
    edges[a-1][b-1] = c
    edges[b-1][a-1] = c

G = csgraph_from_dense(edges, null_value=float('INF'))
dist = floyd_warshall(G)

L_edges = [[float('INF')]*n for _ in range(n)]
for i in range(n-1):
    for j in range(i, n):
        if dist[i][j] <= energy:
            L_edges[i][j] = 1
            L_edges[j][i] = 1

G = csgraph_from_dense(L_edges, null_value=0)
answers = floyd_warshall(G)

Q = int(input())
for i in range(Q):
    s, t = map(int, input().split())
    ans = answers[s-1][t-1] - 1
    print(int(ans))

Submission status: Runtime Error

Solution code:
d_matrix = [[(-1, 10**10)] * (n+1) for _ in range(n+1)]
for i in range(n):
    d = [(-1, 10**10)] * (n+1)
    d[i+1] = (l, 0)
    while True:
        update = False
        for abc in edge_lst:
            a, b, c = abc
            if d[a][1] != 10**10:
                if d[a][0] < c:
                    cnt = d[a][1] + 1
                    f = l - c
                else:
                    cnt = d[a][1]
                    f = d[a][0] - c
                if d[b][1] == cnt:
                    if d[b][0] <= f:
                        d[b] = (f, cnt)
                        update = True
                if d[b][1] > cnt:
                    d[b] = (f, cnt)
                    update = True
        if not update:
            break
        d_matrix[i+1] = d

Submission status: Runtime Error

Solution code:
import numba
import numpy as np
INFTY = 10**12
@numba.jit
def wf(H):
    d = ap.array([[INFTY for _ in range(N+1)] for _ in range(N+1)])
    for i in range(1,N+1):
        d[i][i] = 0
        if i in H:
            for x in H[i]:
                j,c = x[0],x[1]
                d[i][j] = c
    for k in range(1,N+1):
        for i in range(1,N+1):
            for j in range(1,N+1):
                d[i][j] = min(d[i][j],d[i][k]+d[k][j])
    return d
N,M,L = map(int,input().split())
G = {}
for _ in range(M):
    A,B,C = map(int,input().split())
    if A not in G:
        G[A] = []
    G[A].append((B,C))
    if B not in G:
        G[B] = []
    G[B].append((A,C))
d1 = wf(G)
F = {}
for i in range(1,N):
    for j in range(i+1,N+1):
        if d1[i][j]<=L:
            if i not in F:
                F[i] = []
            F[i].append((j,1))
            if j not in F:
                F[j] = []
            F[j].append((i,1))
d2 = wf(F)
Q = int(input())
for _ in range(Q):
    s,t = map(int,input().split())
    if d2[s][t]<INFTY:
        print(d2[s][t]-1)
    else:
        print(-1)

Submission status: Runtime Error

Solution code:
import numba
INFTY = 10**12
@numba.jit
def wf(H):
    d = [[INFTY for _ in range(N+1)] for _ in range(N+1)]
    for i in range(1,N+1):
        d[i][i] = 0
        if i in H:
            for x in H[i]:
                j,c = x[0],x[1]
                d[i][j] = c
    for k in range(1,N+1):
        for i in range(1,N+1):
            for j in range(1,N+1):
                d[i][j] = min(d[i][j],d[i][k]+d[k][j])
    return d
N,M,L = map(int,input().split())
G = {}
for _ in range(M):
    A,B,C = map(int,input().split())
    if A not in G:
        G[A] = []
    G[A].append((B,C))
    if B not in G:
        G[B] = []
    G[B].append((A,C))
d1 = wf(G)
F = {}
for i in range(1,N):
    for j in range(i+1,N+1):
        if d1[i][j]<=L:
            if i not in F:
                F[i] = []
            F[i].append((j,1))
            if j not in F:
                F[j] = []
            F[j].append((i,1))
d2 = wf(F)
Q = int(input())
for _ in range(Q):
    s,t = map(int,input().split())
    if d2[s][t]<INFTY:
        print(d2[s][t]-1)
    else:
        print(-1)

Submission status: Runtime Error

Solution code:
N,M,L = map(int, input().split())
A = [0]*M
B = [0]*M
C = [0]*M
for i in range(M):
    A[i], B[i], C[i] = map(int, input().split())
    
Q = int(input())
qlist = [[int(q) for q in input().split()] for _ in range(Q)]

INF = 10**13
d = [[INF]*N for _ in range(N)]
for i in range(M):
    d[A[i]-1][B[i]-1] = C[i]
    d[B[i]-1][A[i]-1] = C[i]
    d[i][i] = 0
        

# Warshall-Floyd法
# DP
for k in range(N):
    for i in range(N):
        for j in range(N):
            d[i][j] = min(d[i][j], d[i][k]+d[k][j])

d2 = [[INF]*N for _ in range(N)]
for i in range(N):
    for j in range(N):
        if i == j:
            d2[i][j] = 0
        elif d[i][j] <= L:
            d2[i][j] = 1
            
for i in range(N):
    for j in range(N):
        for k in range(N):
            d2[i][j] = min(d2[i][j], d2[i][k]+d2[k][j])
                
for i in range(Q):
    s = qlist[i][0]-1
    t = qlist[i][1]-1
    ans = d2[s][t]
    if ans >= INF:
        print(-1)
    else:
        print(ans-1)

Submission status: Runtime Error

Solution code:
#######################3
N, M, L = map(int, input().split())
ABC = [list(map(int, input().split())) for _ in range(M)]
Q = int(input())
st = [list(map(int, input().split())) for _ in range(Q)]
###################


##########街までの距離をグラフにする、一旦無限大で初期化#############
d = [[float('inf') for _ in range(N)] for _ in range(N)]
#街までの距離を埋める
for i in range(M):
  d[ABC[i][0] - 1][ABC[i][1] - 1] = ABC[i][2]
  d[ABC[i][1] - 1][ABC[i][0] - 1] = ABC[i][2]
#同じ街の距離は0で埋める
for i in range(N):
  d[i][i] = 0
########################################
print(d)

####################################
#最短距離は出せる、給油回数が出せない
def search(s, g, gass):
  length = [float('inf')]
  for i in range(N):
    if d[s][i] == 'inf' or d[s][i] == 0:
    #if d[s][i] == 'inf' or d[s][i] == 0 or d[s][i] > L:
      #return 'inf'
      continue
    elif i == g:
      print("aa")
      return d[s][i]
    else:
      length.append(search(i, g, L))
      return min(length) + d[s][i]

    return 'inf'


###################################
for i in range(Q):
  start = st[i][0] - 1
  goal = st[i][1] - 1
  #探索関数を呼び出す
  print(search(start, goal, L))

Submission status: Runtime Error

Solution code:
#################################
##ワーシャルフロイド法 n~3
#################################
def warshall_floyd(n,d):
    #d[i][j]: iからjへの最短距離
    for k in range(n):
        for i in range(n):
            for j in range(n):
                d[i][j] = min(d[i][j],d[i][k] + d[k][j])
    return d
##############################
from scipy.sparse.csgraph import csgraph_from_dense,dijkstra,floyd_warshall
import sys
def I(): return int(sys.stdin.readline())
def LI(): return list(map(int,sys.stdin.readline().split()))
mod = 10**9 + 7
inf = float('inf')
ans = int(0)
N,M,L =LI()
s = []
t = []
dp = [[inf] * (N) for _ in range(N)]
for i in range(M):
    a, b, c = map(int, input().split())
    dp[a-1][b-1] = c
    dp[b-1][a-1] = c
Q = I()
for i in range(Q):
    a,b = LI()
    s.append(a-1)
    t.append(b-1)

for i in range(N):
    dp[i][i] = 0

#print(warshall_floyd(N,dp))
#d1 = [[0] * (N) for _ in range(N)]
#d1 = warshall_floyd(N,dp)
G = csgraph_from_dense(dp, null_value=10**9)
d1 = floyd_warshall(G)

newdp = [[inf] * (N) for _ in range(N)]
for i in range(N):
    for j in range(i+1,N):
        if d1[i][j]<=L:
            newdp[i][j] = 1
            newdp[j][i] = 1

for i in range(N):
    newdp[i][i] = 0
#print(newdp)
#print(warshall_floyd(N,newdp))
#d2 = [[0] * (N) for _ in range(N)]
#d2 = warshall_floyd(N,newdp)
G = csgraph_from_dense(newdp, null_value=10**9)
d2 = floyd_warshall(G)

for i in range(Q):
    ans = d2[s[i]][t[i]]-1
    if ans!= inf:
        print(int(ans))
    else:
        print("-1")

Submission status: Runtime Error

Solution code:
#!/usr/bin/env python3
import sys
input = lambda: sys.stdin.readline()[:-1]
sys.setrecursionlimit(10**8)
INF = 100100100
n, m, l = map(int, input().split())
rinsetsu = [[INF]*n for i in range(n)]
for i in range(m):
    a, b, c = map(int, input().split())
    rinsetsu[a-1][b-1] = c
    rinsetsu[b-1][a-1] = c
for k in range(n):
    for i in range(n):
        for j in range(n):
            rinsetsu[i][j]=min(rinsetsu[i][j],rinsetsu[i][k]+rinsetsu[j][k])
for i in range(n):
    for j in range(n):
        rinsetsu[i][j]=1 if rinsetsu[i][j]<=l else INF
for k in range(n):
    for i in range(n):
        for j in range(n):
            rinsetsu[i][j] = min(rinsetsu[i][j], rinsetsu[i][k]+rinsetsu[j][k])
q=int(input())
for i in range(q):
    s,g=map(int,input().split())
    s-=1;g-=1
    print(rinsetsu[s][g]-1 if rinsetsu[i][j]!=INF else -1)

Submission status: Runtime Error

Solution code:
import sys
input = sys.stdin.readline

path = [[float("inf") for i in range(301)] for i in range(301)]
def dijkstra(s,n,l):
    d = [float("inf")] * n
    used = [False] * n
    d[s] = 0
    
    while True:
        v = -1
        for i in range(n):
            if (not used[i]) and (v == -1):
                v = i
            elif (not used[i]) and d[i] < d[v]:
                v = i
        if v == -1:
            break
        used[v] = True
        dist_v = d[v]
        for j, weight in enumerate(path[v]):
            alt = dist_v + weight
            r = (dist_v - 1) // l
            if r != ((alt - 1) // l) and dist_v != 0:
                alt = (r + 1) * l + weight         
            d[j] = min(d[j],alt)
    return d

n,m,l = map(int, input().split())
ans_list = []
for i in range(m):
  a,b,cost = map(int, input().split())
  a -= 1
  b -= 1
  if cost <= l:
    path[a][b] = cost
    path[b][a] = cost
for s in range(n):
  ans_list.append(dijkstra(s,n,l))
q = int(input())

for i in range(q):
  s,t = map(int, input().split())
  ans = ans_list[s-1][t-1]
  if ans == float("inf"):
    ans = -1
  else:
    ans = (ans - 1) // l
  print(ans)

Submission status: Runtime Error

Solution code:
import java.util.*;
import java.io.*;

public class Main {
    static int N;
    static int M;
    static int L;
    static int Q;
    static long[][] wf;
    static long[][] ans;
    static Queue<Pair> fixed = new LinkedList<Pair>();
    static List<List<Integer>> zero;
    public static void main(String[] args) {
        N = sc.nextInt();
        M = sc.nextInt();
        L = sc.nextInt();
        wf = new long[N][N];
        ans = new long[N][N];
        zero = new ArrayList<List<Integer>>(N);
        for (int i = 0; i < N; i++) {
            zero.add(new ArrayList<Integer>());
        }
        //inf initialize
        for (int i = 0; i < N; i++) {
            for (int j = 0; j < N; j++) {
                wf[i][j] = Integer.MAX_VALUE;
                ans[i][j] = Integer.MAX_VALUE;
            }
        }
        for (int i = 0; i < M; i++) {
            int a = sc.nextInt() - 1;
            int b = sc.nextInt() - 1;
            int c = sc.nextInt();
            wf[a][b] = wf[b][a] = c;
        }
        //wf
        for (int k = 0; k < N; k++) {
            for (int i = 0; i < N; i++) {
                for (int j = 0; j < N; j++) {
                    wf[i][j] = Math.min(wf[i][j], wf[i][k] + wf[k][j]);
                }
            }
        }
        for (int i = 0; i < N; i++) {
            for (int j = 0; j < N; j++) {
                if (wf[i][j] <= L) {
                    ans[i][j] = 0;
                    ans[j][i] = 0;
                    fixed.offer(new Pair(i,j));
                    fixed.offer(new Pair(j,i));
                    zero.get(i).add(j);
                    zero.get(j).add(i);
                }
            }
        }
        while (fixed.size() > 0) {
            Pair p = fixed.poll();
            for (int k : zero.get(p.j)) {
                long newValue = ans[p.i][p.j] + 1;
                if (ans[p.i][k] > newValue) {
                    ans[p.i][k] = Math.min(ans[p.i][k], ans[p.i][p.j] + 1);
                    fixed.offer(new Pair(p.i, k));
                }
            }
        }
        Q = sc.nextInt();
        // writer.println(Q);
        //Query
        for (int i = 0; i < Q; i++) {
            int s = sc.nextInt() - 1;
            int t = sc.nextInt() - 1;
            long answer = (ans[s][t] == Integer.MAX_VALUE) ? -1 : ans[s][t];
            writer.println(answer); 
        }
        writer.flush();
        
        
    }
    static class Pair {
        public int i;
        public int j;
        public Pair(int i, int j) {
            this.i = i;
            this.j = j;
        }
    }

    static final FastScanner sc = new FastScanner(System.in);
    static PrintWriter writer = new PrintWriter(System.out);

    static class FastScanner {
        Reader input;
 
        FastScanner() {
            this(System.in);
        }
 
        FastScanner(InputStream stream) {
            this.input = new BufferedReader(new InputStreamReader(stream));
        }
 
        int nextInt() {
            return (int) nextLong();
        }
 
        long nextLong() {
            try {
                int sign = 1;
                int b = input.read();
                while ((b < '0' || '9' < b) && b != '-' && b != '+') {
                    b = input.read();
                }
                if (b == '-') {
                    sign = -1;
                    b = input.read();
                } else if (b == '+') {
                    b = input.read();
                }
                long ret = b - '0';
                while (true) {
                    b = input.read();
                    if (b < '0' || '9' < b) return ret * sign;
                    ret *= 10;
                    ret += b - '0';
                }
            } catch (IOException e) {
                e.printStackTrace();
                return -1;
            }
        }
 
        double nextDouble() {
            try {
                double sign = 1;
                int b = input.read();
                while ((b < '0' || '9' < b) && b != '-' && b != '+') {
                    b = input.read();
                }
                if (b == '-') {
                    sign = -1;
                    b = input.read();
                } else if (b == '+') {
                    b = input.read();
                }
                double ret = b - '0';
                while (true) {
                    b = input.read();
                    if (b < '0' || '9' < b) break;
                    ret *= 10;
                    ret += b - '0';
                }
                if (b != '.') return sign * ret;
                double div = 1;
                b = input.read();
                while ('0' <= b && b <= '9') {
                    ret *= 10;
                    ret += b - '0';
                    div *= 10;
                    b = input.read();
                }
                return sign * ret / div;
            } catch (IOException e) {
                e.printStackTrace();
                return Double.NaN;
            }
        }
 
        char nextChar() {
            try {
                int b = input.read();
                while (Character.isWhitespace(b)) {
                    b = input.read();
                }
                return (char) b;
            } catch (IOException e) {
                e.printStackTrace();
                return 0;
            }
        }
 
        String nextStr() {
            try {
                StringBuilder sb = new StringBuilder();
                int b = input.read();
                while (Character.isWhitespace(b)) {
                    b = input.read();
                }
                while (b != -1 && !Character.isWhitespace(b)) {
                    sb.append((char) b);
                    b = input.read();
                }
                return sb.toString();
            } catch (IOException e) {
                e.printStackTrace();
                return "";
            }
        }
    }
    //FAST SCANNER END HERE
}

Submission status: Runtime Error

Solution code:
import math

n,m,l=map(int,raw_raw_input().split())
INF=(10**9)+1

g=[]
f=[]
for i in xrange(n):
    g.append([INF]*(n))
    f.append([INF]*(n))

for i in xrange(len(g)):
    for j in xrange(len(g)):
        if i==j:
            g[i][j]=0
            f[i][j]=0

for i in xrange(m):
    a,b,c=map(int,raw_input().split())
    g[a-1][b-1]=c
    g[b-1][a-1]=c
    f[a-1][b-1]=c
    f[b-1][a-1]=c

for k in xrange(n):
    for i in xrange(n):
        for j in xrange(n):
            g[i][j]=min(g[i][j],g[i][k]+g[k][j])
            f[i][j]=min(f[i][j],f[i][k]+f[k][j])

for i in xrange(n):
    for j in xrange(n):
        if f[i][j]<=l:
            g[i][j]=1
        else:
            g[i][j]=INF
        if i==j:
            g[i][j]=0

for k in xrange(n):
    for i in xrange(n):
        for j in xrange(n):
            g[i][j]=min(g[i][j],g[i][k]+g[k][j])

q=int(raw_input())
for i in xrange(q):
    s,t=map(int,raw_input().split())
    u=g[s-1][t-1]

    if u>=INF:
        print (-1)
    else:
        print (u-1)

Submission status: Runtime Error

Solution code:
def use_fast_io():
    global input
    import io
    import sys
    f = io.BytesIO(sys.stdin.buffer.read())
    input = f.readline


use_fast_io()

from scipy.sparse.csgraph import floyd_warshall
import numpy as np


def solve():
    n, m, l = map(int, input().split())
    graph = np.full((n, n), 10 ** 10)
    for _ in range(m):
        s, t, w = map(int, input().split())
        if w <= l:
            graph[s - 1][t - 1] = graph[t - 1][s - 1] = w
    graph = floyd_warshall(graph, directed=False)
    graph = floyd_warshall(graph <= l, directed=False)
    graph[np.isinf(graph)] = 0
    Q = int(input())
    ans = []
    for _ in range(Q):
        s, t = map(int, input().split())
        ans.append(int(graph[s - 1][t - 1]) - 1)
    print(*ans, sep='\n')


solve()

if __name__ == '__main__':
    solve()

Submission status: Runtime Error

Solution code:
def use_fast_io():
    global input
    import io
    import sys
    f = io.BytesIO(sys.stdin.buffer.read())
    input = f.readline


#use_fast_io()

from scipy.sparse.csgraph import floyd_warshall
import numpy as np


def solve():
    n, m, l = map(int, input().split())
    graph = np.full((n, n), 10 ** 10)
    for _ in range(m):
        s, t, w = map(int, input().split())
        if w <= l:
            graph[s - 1][t - 1] = graph[t - 1][s - 1] = w
    graph = floyd_warshall(graph, directed=False)
    graph = floyd_warshall(graph <= l, directed=False)
    graph[np.isinf(graph)] = 0
    Q = int(input())
    ans = []
    for _ in range(Q):
        s, t = map(int, input().split())
        ans.append(int(graph[s - 1][t - 1]) - 1)
    print(*ans, sep='\n')


solve()

if __name__ == '__main__':
    solve()

Submission status: Runtime Error

Solution code:
import io
import sys
from scipy.sparse.csgraph import floyd_warshall
import numpy as np

N, M, L = map(int, io.BytesIO(sys.stdin.buffer.read()).readline().split())
graph = np.full((N, N), 10 ** 10)
for _ in range(M):
    s, t, w = map(int, input().split())
    if w <= L:
        graph[s - 1][t - 1] = graph[t - 1][s - 1] = w
graph = floyd_warshall(graph, directed=False)
graph = floyd_warshall(graph <= L, directed=False)
graph[np.isinf(graph)] = 0

Q = int(input())
ans = []
for _ in range(Q):
    s, t = map(int, input().split())
    ans.append(int(graph[s - 1][t - 1]) - 1)
print(*ans, sep='\n')

Submission status: Runtime Error

Solution code:
from scipy.sparse import*
i=lambda:tuple(map(int,input().split()))
f=csgraph.floyd_warshall
n,m,l=i()
d=eval('[0]*-~n,'*-~n)
exec('a,b,c=i();d[a][b]=c;'*m)
d=f(f(d,0)<=l)
d*=d<n
for _ in'_'*i()[0]:print(int(d[i()])-1)

Submission status: Runtime Error

Solution code:
import sys
input = sys.stdin.readline
sys.setrecursionlimit(10 ** 7)

def dijkstra(s,n,cost,l):
    d = [float("inf")] * n
    used = [False] * n
    d[s] = 0
    
    while True:
        v = -1
        for i in range(n):
            if (not used[i]) and (v == -1):
                v = i
            elif (not used[i]) and d[i] < d[v]:
                v = i
        if v == -1:
            break
        used[v] = True
        dist_v = d[v]
        for j in range(n):
            weight = cost[v][j]
            alt = dist_v + weight
            r = (dist_v - 1) // l
            if (r != ((alt - 1) // l) and dist_v != 0:
                alt = (r + 1) * l + weight         
            d[j] = min(d[j],alt)
    return d
 
n,m,l = map(int, input().split())
abc = [list(map(int, input().split())) for i in range(m)]
q = int(input())
st = [list(map(int, input().split())) for i in range(q)]
path = [[float("inf") for i in range(n)] for i in range(n)]
ans_list = []
for i in abc:
  a,b,cost = i[0]-1, i[1]-1, i[2]
  if cost <= l:
    path[a][b] = cost
    path[b][a] = cost
for s in range(n):
  ans_list.append(dijkstra(s,n,path,l))
for i in st:
  s, t = i[0] - 1, i[1] - 1
  ans = ans_list[s][t]
  if ans == float("inf"):
    ans = -1
  else:
    ans = (ans - 1) // l
  print(ans)

Submission status: Runtime Error

Solution code:
# ABC143E - Travel by Car
def floyd_warshall(dist):
    """
    Compute the shortest paths of all pairs and modify dist.
    """
    for i in range(N):  # intermediate point
        for j, c2 in enumerate(dist[j][i] for j in range(N)):  #  source
            for k, (c1, c3) in enumerate(zip(dist[j], dist[i])):  # target
                if c2 + c3 < c1:
                    dist[j][k] = c2 + c3
                    

def main():
    # FW -> once more FW to edges <= L
    global N
    N, M, L, *X = map(int, open(0).read().split())
    ABC, ST = X[: 3 * M], X[3 * M + 1 :]
    INF = float("inf")
    dist = [[INF] * (N + 1) for _ in range(N + 1)]
    for i in range(N + 1):
        dist[i][i] = 0
    for v, u, cost in zip(*[iter(ABC)] * 3):
        dist[v][u] = dist[u][v] = cost
    dist = floyd_warshall(dist)

    # assume distance within L as 1 and compute the number of fueling
    modified_dist = [[1 if x <= L else INF for x in d] for d in dist]
    modified_dist = floyd_warshall(modified_dist)
    ans = [
        modified_dist[s][t] - 1 if modified_dist[s][t] != INF else -1
        for s, t in zip(*[iter(ST)] * 2)
    ]
    print("\n".join(map(str, ans)))


if __name__ == "__main__":
    main()

Submission status: Runtime Error

Solution code:
from scipy.sparse.csgraph import floyd_warshall
N,M,L=map(int,input().split())
inf=10**9+1

distance=[[inf for n in range(N)] for n in range(N)]
for n in range(N):
    distance[n][n]=0
for m in range(M):
    a,b,c=map(int,input().split())
    distance[a-1][b-1]=c
    distance[b-1][a-1]=c
distance=floyd_warshall

distance2=[[inf for n in range(N)] for n in range(N)]
for i in range(N):
    for j in range(N):
        if distance[i][j]<=L:
            distance2[i][j]=1
for n in range(N):
    distance2[n][n]=0
distance2=floyd_warshall(distance2)

Q=int(input())
for q in range(Q):
    s,t=map(int,input().split())
    if distance2[s-1][t-1]==inf:
        print(-1)
    else:
        print(distance2[s-1][t-1]-1)

Submission status: Runtime Error

Solution code:

# -*- coding: utf-8 -*-
import bisect
import heapq
import math
import random
import sys
from collections import Counter, defaultdict, deque
from decimal import ROUND_CEILING, ROUND_HALF_UP, Decimal
from functools import lru_cache, reduce
from itertools import combinations, combinations_with_replacement, product, permutations
from operator import add, mul, sub

sys.setrecursionlimit(100000)
input = sys.stdin.readline


def read_int():
    return int(input())


def read_int_n():
    return list(map(int, input().split()))


def read_float():
    return float(input())


def read_float_n():
    return list(map(float, input().split()))


def read_str():
    return input().strip()


def read_str_n():
    return list(map(str, input().split()))


def error_print(*args):
    print(*args, file=sys.stderr)


def mt(f):
    import time

    def wrap(*args, **kwargs):
        s = time.time()
        ret = f(*args, **kwargs)
        e = time.time()

        error_print(e - s, 'sec')
        return ret

    return wrap


def warshall_floyd(g):
    d = defaultdict(dict)
    V = list(g.keys())
    for v in g.values():
        V.extend(list(v))
    V = set(V)
    for i in V:
        for j in V:
            if i in g and j in g[i]:
                d[i][j] = g[i][j]
            else:
                d[i][j] = sys.maxsize
    for k in g:
        for i in g:
            for j in g:
                if d[i][j] > d[i][k] + d[k][j]:
                    d[i][j] = d[i][k] + d[k][j]

    return d

@mt
def slv(N, M, L, ABC, Q, ST):

    g = defaultdict(dict)
    for a, b, c in ABC:
        g[a][b] = c
        g[b][a] = c
    
    d = warshall_floyd(g)
    gg = defaultdict(dict)
    for u in range(1, N+1):
        for v in range(1, N+1):
            if d[u][v] <= L:
                gg[u][v] = 1
    dd = warshall_floyd(gg)

    for s, t in ST:
        if s in dd and t in dd[s]:
            print(dd[s][t]-1)
        else:
            print(-1)



def main():
    N, M, L = read_int_n()
    ABC = [read_int_n() for _ in range(M)]
    Q = read_int()
    ST = [read_int_n() for _ in range(Q)]
    (slv(N, M, L, ABC, Q, ST))

    # N = 300
    # M = (N*(N-1))//2
    # L = random.randint(1, 10**9)
    # ABC = []
    # for i in range(1, N+1):
    #     for j in range(i+1, N+1):
    #         ABC.append([i, j, random.randint(1, 10**9)])
    
    # ST = []
    # for i in range(1, N+1):
    #     for j in range(1, N+1):
    #         if i == j:
    #             continue
    #         ST.append([i, j])
    # Q = len(ST)
    # (slv(N, M, L, ABC, Q, ST))


if __name__ == '__main__':
    main()