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: Time Limit Exceeded

Solution code:
def warshal_floyd(d,N):
    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

def main():
    N, M, L = map(int, input().split())
    d = [[float('inf')] * N for _ in range(N)]
    for _ in range(M):
        A, B, C = map(int, input().split())
        A -= 1
        B -= 1
        d[A][B] = C
        d[B][A] = C

    e = warshal_floyd(d,N)
    f = [[float('inf')] * N for _ in range(N)]
    for i in range(N):
        for j in range(N):
            if e[i][j] <= L:
                f[i][j] = 1

    g = warshal_floyd(f,N)
    Q = int(input())
    for _ in range(Q):
        s, t = map(int, input().split())
        s -= 1
        t -= 1
        if g[s][t] == float('inf'):
            print(-1)
        else:
            print(g[s][t]-1)
    



if __name__ == "__main__":
    main()

Submission status: Time Limit Exceeded

Solution code:
n, m, l = map(int, input().split())
mw =[[float('inf')] * n for _ in range(n)]
for _ in range(m):
    a, b, c = map(int, input().split())
    mw[a-1][b-1] = c
    mw[b-1][a-1] = c

def warshall_floyd(d): # d: 隣接行列
    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

d = warshall_floyd(mw)
mw =[[float('inf')] * n for _ in range(n)]
for i in range(n):
    for j in range(n):
        if d[i][j] <= l:
            mw[i][j] = 1
dd = warshall_floyd(mw)

q = int(input())
for _ in range(q):
    s, t = map(int, input().split())
    ans = dd[s-1][t-1]-1
    if ans > 10 ** 10:
        print(-1)
    else:
        print(ans)

Submission status: Time Limit Exceeded

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

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())
path = [[float("inf") for i in range(n)] for i in range(n)]
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,path,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: Time Limit Exceeded

Solution code:
N, M, L = map(int, input().split())
edges = [list(map(int, input().split())) for _ in range(M)]
Q = int(input())
X = [list(map(int, input().split())) for _ in range(Q)]

graph = [[float('inf')] * N for _ in range(N)]

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

for u, v, l in edges:
    graph[u - 1][v - 1] = l
    graph[v - 1][u - 1] = l

for k in range(N):
    for i in range(N):
        if graph[i][k] == float('inf'):
            continue
        for j in range(N):
            if graph[k][j] == float('inf'):
                continue
            graph[i][j] = min(graph[i][j], graph[i][k] + graph[k][j])

cnt = [[float('inf')] * N for _ in range(N)]

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

for i in range(N):
    for j in range(N):
        if i == j:
            continue
        if graph[i][j] <= L:
            cnt[i][j] = 1
            cnt[j][i] = 1

for k in range(N):
    for i in range(N):
        if cnt[i][k] == float('inf'):
            continue
        for j in range(N):
            if cnt[k][j] == float('inf'):
                continue
            cnt[i][j] = min(cnt[i][j], cnt[i][k] + cnt[k][j])

for s, t in X:
    if cnt[s - 1][t - 1] == float('inf'):
        print(-1)
    else:
        print(cnt[s - 1][t - 1] - 1)

Submission status: Time Limit Exceeded

Solution code:
N,M,L = map(int, input().split())
INF = float("inf")
# 初期化
d = [[INF]*N for i in range(N)]
for i in range(N):
    d[i][i] = 0
for i in range(M):
    a,b,c = map(int, input().split())
    a -= 1
    b -= 1
    # 多重辺の場合はMIN
    d[a][b] = c
    d[b][a] = c
# 最適化(わーしゃゆふよいど)
for k in range(N):
    for i in range(N):
        # 左右は対称だろう
        for j in range(i+1,N):
            d[i][j] = min(d[i][j], d[i][k] + d[k][j])
            d[j][i] = d[i][j]

# 初期化2
d2 = [[INF]*N for i in range(N)]
for i in range(N):
    d2[i][i] = 0
for i in range(N):
    for j in range(N):
        # 給油できるところに辺を張る
        if d[i][j] <= L:
            d2[i][j] = 1
for k in range(N):
    for i in range(N):
        for j in range(i+1,N):
            d2[i][j] = min(d2[i][j], d2[i][k] + d2[k][j])
            d2[j][i] = d2[i][j]
            

#query
Q = int(input())
for i in range(Q):
    l  = list(map(int, input().split()))
    s = min(l)-1
    t = max(l)-1
    
    ans = d2[s][t]-1
    if ans == INF:
        ans = -1
    print(ans)

Submission status: Time Limit Exceeded

Solution code:
from collections import deque
N,M,L = map(int, input().split())
INF = float("inf")
# 初期化
d = [[INF]*N for i in range(N)]
for i in range(N):
    d[i][i] = 0
for i in range(M):
    a,b,c = map(int, input().split())
    a -= 1
    b -= 1   
    # 多重辺の場合はMIN
    d[a][b] = c
    d[b][a] = c
# 最適化(わーしゃゆふよいど)
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])

# 初期化2
d2 = [[INF]*N for i in range(N)]
for i in range(N):
    d2[i][i] = 0
for i in range(N):
    for j in range(N):
        # 給油できるところに辺を張る
        if d[i][j] <= L:
            d2[i][j] = 1
for k in range(N):
    for i in range(N):
        for j in range(N):
            d2[i][j] = min(d2[i][j], d2[i][k] + d2[k][j])

#query
Q = int(input())
for i in range(Q):
    s,t  = map(int, input().split())
    s -= 1
    t -= 1
    ans = d2[s][t]-1
    if ans == INF:
        ans = -1
    print(ans)

Submission status: Time Limit Exceeded

Solution code:
from collections import defaultdict,deque
import sys,heapq,bisect,math,itertools,string,queue,copy,time
sys.setrecursionlimit(10**8)
INF = float('inf')
mod = 10**9+7
eps = 10**-7
def inp(): return int(sys.stdin.readline())
def inpl(): return list(map(int, sys.stdin.readline().split()))
def inpl_str(): return list(sys.stdin.readline().split())

N,M,L = inpl()
cost = [[INF]*N for _ in range(N)]
for i in range(N):
    cost[i][i] = 0

for _ in range(M):
    a,b,c = inpl()
    a,b = a-1,b-1
    cost[a][b] = c
    cost[b][a] = c

for k in range(N):
    for i in range(N):
        for j in range(N):
            cost[i][j]=min(cost[i][j],cost[i][k]+cost[k][j])

# print(cost)

for i in range(N):
    for j in range(N):
        if cost[i][j] == 0:
            cost[i][j] = 0
        elif cost[i][j] <= L:
            cost[i][j] = 1
        else:
            cost[i][j] = INF

# print(cost)

for k in range(N):
    for i in range(N):
        for j in range(N):
            cost[i][j]=min(cost[i][j],cost[i][k]+cost[k][j])


Q = inp()
ans = []
for _ in range(Q):
    s,t = inpl()
    tmp = cost[s-1][t-1]
    if tmp == INF:
        ans.append(-1)
    else:
        ans.append(tmp-1)

print('\n'.join(map(str,ans)))

Submission status: Time Limit Exceeded

Solution code:
import sys

input = sys.stdin.readline


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


def read_is(n=1):
    return [read_i() for _ in range(n)]


class Graph:
    def __init__(self, n_nodes):
        self.n_nodes = n_nodes
        self.edges = [[float('inf')] * n_nodes for _ in range(n_nodes)]

    def add_edge(self, s, t, d=None, undirected=False):
        if d is None:
            d = 1
        self.edges[s][t] = d
        if undirected:
            self.edges[t][s] = d


class FloydWarshall:
    def __init__(self, graph):
        self.graph = graph
        self.distances = [[float('inf')] * graph.n_nodes
                          for _ in range(graph.n_nodes)]
        self.nexts = [[None] * graph.n_nodes for _ in range(graph.n_nodes)]
        self._init()

    def _init(self):
        for x in range(self.graph.n_nodes):
            self.distances[x][x] = 0
        for source in range(self.graph.n_nodes):
            for destination, distance in enumerate(self.graph.edges[source]):
                self.distances[source][destination] = distance
                self.nexts[source][destination] = destination

    def compute_shortest_path_lengths(self):
        for k in range(self.graph.n_nodes):
            for i in range(self.graph.n_nodes):
                for j in range(self.graph.n_nodes):
                    s = self.distances[i][k] + self.distances[k][j]
                    if s < self.distances[i][j]:
                        self.distances[i][j] = s
                        self.nexts[i][j] = self.nexts[i][k]


n, m, l = read_i()
graph = Graph(n)
for _ in range(m):
    a, b, c = read_i()
    if c > l:
        continue
    graph.add_edge(a - 1, b - 1, d=c, undirected=True)
fw = FloydWarshall(graph)
fw.compute_shortest_path_lengths()

graph2 = Graph(n)
for s in range(n):
    for t in range(n):
        if s >= t:
            continue
        if fw.distances[s][t] > l:
            continue
        graph2.add_edge(s, t, d=1, undirected=True)
fw = FloydWarshall(graph2)
fw.compute_shortest_path_lengths()

q = int(input())
for _ in range(q):
    s, t = read_i()
    s -= 1
    t -= 1
    d = fw.distances[s][t] - 1
    if d == float('inf'):
        print(-1)
    else:
        print(d)

Submission status: Time Limit Exceeded

Solution code:
import sys

sys.setrecursionlimit(10 ** 6)
input = sys.stdin.readline

def main():
    n, m, l = map(int, input().split())
    inf = 1001001001
    dist = [[inf] * n for _ in range(n)]
    for _ in range(m):
        a, b, c = map(int, input().split())
        a, b = a - 1, b - 1
        dist[a][b] = dist[b][a] = c
    for w in range(n):
        for u in range(n):
            for v in range(n):
                dist[u][v] = min(dist[u][v], dist[u][w] + dist[w][v])
    dist2 = [[inf] * n for _ in range(n)]
    for u in range(n):
        for v in range(n):
            if dist[u][v] <= l: dist2[u][v] = 1
    for w in range(n):
        for u in range(n):
            for v in range(n):
                dist2[u][v] = min(dist2[u][v], dist2[u][w] + dist2[w][v])

    q = int(input())
    for _ in range(q):
        s, t = map(lambda x: int(x) - 1, input().split())
        ans = dist2[s][t]
        if ans == inf:
            print(-1)
        else:
            print(ans - 1)

main()

Submission status: Time Limit Exceeded

Solution code:
n,m,l=map(int,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: Time Limit Exceeded

Solution code:
import math

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

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

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

for i in range(m):
    a,b,c=map(int,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 range(n):
    for i in range(n):
        for j in range(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 range(n):
    for j in range(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 range(n):
    for i in range(n):
        for j in range(n):
            g[i][j]=min(g[i][j],g[i][k]+g[k][j])

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

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

Submission status: Time Limit Exceeded

Solution code:
N, M, L = map(int, input().split())

dist = [[float('inf')] * N for _ in range(N)]
for i in range(N):
    dist[i][i] = 0

for i in range(M):
    A, B, C = map(int, input().split())
    dist[A-1][B-1] = C
    dist[B-1][A-1] = C

for k in range(N):
    for i in range(N):
        for j in range(N):
            if dist[i][j] > dist[i][k] + dist[k][j]:
                dist[i][j] = dist[i][k] + dist[k][j]

dist2 = [[float('inf')] * N for _ in range(N)]

for i in range(N):
    for j in range(N):
        if dist[i][j] <= L:
            dist2[i][j] = 1

for k in range(N):
    for i in range(N):
        for j in range(N):
            if dist2[i][j] > dist2[i][k] + dist2[k][j]:
                dist2[i][j] = dist2[i][k] + dist2[k][j]

for i in range(int(input())):
    s, t = map(int, input().split())
    if dist2[s-1][t-1] == float('inf'):
        print(-1)
    else:
        print(dist2[s-1][t-1]-1)

Submission status: Time Limit Exceeded

Solution code:
import queue

N, M, L = map(int, input().split())

dist = [[float('inf')] * N for _ in range(N)]
for i in range(M):
    A, B, C = map(int, input().split())
    dist[A-1][B-1] = C
    dist[B-1][A-1] = C

for k in range(N):
    for i in range(N):
        for j in range(N):
            if dist[i][j] > dist[i][k] + dist[k][j]:
                dist[i][j] = dist[i][k] + dist[k][j]

near = [[] for _ in range(N)]
for i in range(N-1):
    for j in range(i+1, N):
        if dist[i][j] <= L:
            near[i].append(j)
            near[j].append(i)

def BFS(s, t):
    dist2 = [-1] * N
    que = queue.Queue()

    dist2[s] = 0
    que.put(s)
    
    while not que.empty():
        v = que.get()
        for nv in near[v]:
            if dist2[nv] != -1:
                continue
            if v == s:
                dist2[nv] = 0
            else:
                dist2[nv] = dist2[v] + 1
            if nv == t:
                return dist2[nv]
            que.put(nv)
    return -1


for i in range(int(input())):
    s, t = map(int, input().split())
    print(BFS(s-1, t-1))

Submission status: Time Limit Exceeded

Solution code:
import queue

N, M, L = map(int, input().split())

dist = [[float('inf')] * N for _ in range(N)]
for i in range(M):
    A, B, C = map(int, input().split())
    dist[A-1][B-1] = C
    dist[B-1][A-1] = C

for k in range(N):
    for i in range(N):
        for j in range(N):
            if dist[i][j] > dist[i][k] + dist[k][j]:
                dist[i][j] = dist[i][k] + dist[k][j]

near = [[] for _ in range(N)]
for i in range(N-1):
    for j in range(i+1, N):
        if dist[i][j] <= L:
            near[i].append(j)
            near[j].append(i)

def BFS(s, t):
    dist2 = [-1] * N
    que = queue.Queue()

    dist2[s] = 0
    que.put(s)
    
    while not que.empty():
        v = que.get()
        for nv in near[v]:
            if dist2[nv] != -1:
                continue
            if v == s:
                dist2[nv] = 0
            else:
                dist2[nv] = dist2[v] + 1
            if nv == t:
                return dist2[nv]
            que.put(nv)
    return -1


for i in range(int(input())):
    s, t = map(int, input().split())
    print(BFS(s-1, t-1))

Submission status: Time Limit Exceeded

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

Submission status: Time Limit Exceeded

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

Submission status: Time Limit Exceeded

Solution code:
from scipy.sparse import*
i=lambda:tuple(map(int,input().split()))
f=csgraph.dijkstra
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]=0
for _ in'_'*i()[0]:print(int(d[i()])-1)

Submission status: Time Limit Exceeded

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

Submission status: Time Limit Exceeded

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

Submission status: Time Limit Exceeded

Solution code:
from scipy.sparse import*
i=lambda:tuple(map(int,input().split()))
f=csgraph.johnson
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]=0
for _ in'_'*i()[0]:print(int(d[i()])-1)

Submission status: Time Limit Exceeded

Solution code:
from scipy.sparse import*
i=lambda:tuple(map(int,input().split()))
f=csgraph.bellman_ford
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]=0
for _ in'_'*i()[0]:print(int(d[i()])-1)

Submission status: Time Limit Exceeded

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]=0
exec('print(int(d[i()])-1);'*i()[0])

Submission status: Time Limit Exceeded

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>9e9]=0
exec('print(int(d[i()])-1);'*i()[0])

Submission status: Time Limit Exceeded

Solution code:
from scipy.sparse import*
i=lambda: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>9e9]=0
q,=i()
exec('s,t=i();print(int(d[s,t])-1);'*q)

Submission status: Time Limit Exceeded

Solution code:
from scipy.sparse import*
i=lambda: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)
q,=i()
while q:s,t=i();t=d[s,t];print((t<9e9and int(t))-1);q-=1

Submission status: Time Limit Exceeded

Solution code:
from scipy.sparse import*
i=lambda:map(int,input().split())
f=csgraph.floyd_warshall
I=9e9
n,m,l=i()
d=eval('[I]*-~n,'*-~n)
exec('a,b,c=i();d[a][b]=c;'*m)
d=f(d,0)
d[d>l]=I
d[d<I]=1
d=f(d)
d[d>I]=I
q,=i()
exec('s,t=i();print(int(d[s,t]%I)-1);'*q)

Submission status: Time Limit Exceeded

Solution code:
from scipy.sparse import*
f=csgraph.floyd_warshall
I=9e9
i=lambda:map(int,input().split())
n,m,l=i()
d=eval('[I]*-~n,'*-~n)
while m:a,b,c=i();d[a][b]=c;m-=1
d=f(d,0)
d[d>l]=I
d[d<I]=1
d=f(d)
q,=i()
while q:s,t=i();print((I>d[s,t])*int(d[s,t])-1);q-=1

Submission status: Time Limit Exceeded

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: Time Limit Exceeded

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
            if ((dist_v - 1) // l) != ((alt - 1) // l) and dist_v != 0:
                alt = ((dist_v - 1) // l + 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: Time Limit Exceeded

Solution code:
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
            if (dist_v - 1) // l != (alt - 1) // l and dist_v != 0:
                alt = ((dist_v - 1) // l + 1) * l + weight         
            d[j] = min(d[j],alt)
    return d

n,m,l = map(int, input().split())
path = [[float("inf") for i in range(n)] for i in range(n)]
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,path,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: Time Limit Exceeded

Solution code:
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
            if (dist_v - 1) // l != (alt - 1) // l and dist_v != 0:
                alt = ((dist_v - 1) // l + 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_list[s][t] - 1) // l
  print(ans)

Submission status: Time Limit Exceeded

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

N,M,L=map(int,input().split())

E=[[] for i in range(N+1)]

for i in range(M):
    a,b,cost=map(int,input().split())

    E[a].append((b,cost))
    E[b].append((a,cost))


Q=int(input())
Query=[list(map(int,input().split())) for i in range(Q)]

ANS=[[(N+10,0) for i in range(N+1)] for j in range(N+1)]

from collections import deque
import heapq

for start in range(1,N+1):

    ANS[start][start]=(0,0)

    checking=[((0,0),start)]

    while checking:
        #print(checking)
        c,checktown=heapq.heappop(checking)
        h,cost0=c

        if ANS[start][checktown]<c:
            continue

        for to,cost in E[checktown]:
            
            if cost0+cost<=L and (h,cost0+cost)<ANS[start][to]:
                ANS[start][to]=(h,cost0+cost)
                heapq.heappush(checking,((h,cost0+cost),to))

            elif cost<=L and (h+1,cost)<ANS[start][to]:
                ANS[start][to]=(h+1,cost)
                heapq.heappush(checking,((h+1,cost),to))

for x,y in Query:
    if ANS[x][y][0]==N+10:
        print(-1)
    else:
        print(ANS[x][y][0])

Submission status: Time Limit Exceeded

Solution code:
from collections import deque
import sys
import random
input = sys.stdin.readline


n, m, l = map(int, input().split())
info = [list(map(int, input().split())) for i in range(m)]
graph = [[] for i in range(n)]

for i in range(m):
    a, b, cost = info[i]
    if cost > l:
        continue
    a -= 1
    b -= 1
    graph[a].append((b, cost))
    graph[b].append((a, cost))

for i in range(n):
    graph[i] = random.sample(graph[i], len(graph[i]))
    
def dfs(start):
    INF = float("inf")
    visited_t = [INF]*n # 回数, 残り燃料
    visited_l = [0]*n
    visited_t[start] = 0
    q = deque([start])
    while q:
        pos = q.popleft()
        for next_pos, cost in graph[pos]:
            tmp = cost + visited_l[pos]
            times = visited_t[pos]
            next_times = visited_t[next_pos]
            if tmp <= l:
                if next_times > times:
                    q.append(next_pos)
                    visited_t[next_pos] = times
                    visited_l[next_pos] = tmp
                elif next_times == times:
                    if visited_l[next_pos] > tmp:
                        q.append(next_pos)
                        visited_t[next_pos] = times
                        visited_l[next_pos] = tmp
                else:
                    continue
            else:
                tmp = cost
                if next_times > times + 1:
                    q.append(next_pos)
                    visited_t[next_pos] = times + 1
                    visited_l[next_pos] = tmp
                elif next_times == times + 1:
                    if visited_l[next_pos] > tmp:
                        q.append(next_pos)
                        visited_t[next_pos] = times + 1
                        visited_l[next_pos] = tmp
                else:
                    continue
    return visited_t

ans = [None]*n
for i in range(n):
    ans[i] = dfs(i)

INF = float("inf")
q = int(input())
query = [list(map(int, input().split())) for i in range(q)]
for i in range(q):
    a, b = query[i]
    a -= 1
    b -= 1
    tmp = ans[a][b]
    if tmp == INF:
        print(-1)
    else:
        print(tmp)