Buggy python submission (verdict: Time Limit Exceeded):
import heapq
import copy

V, M = map(int, input().split())
d = [0] * V
prev = [0] * V
INF = float('inf')

cost = [[INF] * V for i in range(V)]
for i in range(M):
    a, b, c = map(int,  input().split())
    cost[a - 1][b - 1] = c
    cost[b - 1][a - 1] = c
    
def dijkstra_back(s, t):
    for i in range(V):
        prev[i] = s
        d[i] = INF
    d[s] = 0
    h = []
    heapq.heappush(h, [0, s])
    
    while h != []:
        p = heapq.heappop(h)
        v = p[1]
        if d[v] < p[0]:
            continue
         
        for i in range(V):
            if d[i] > d[v] + cost[v][i]: 
                d[i] = d[v] + cost[v][i]
                heapq.heappush(h, [d[i], i])
                prev[i] = v
        
    path = [t]
    while prev[t] != s:
        path.append(prev[t])
        prev[t] = prev[prev[t]]
    path.append(s)
    path = path[::-1]
    return path

cost2 = copy.deepcopy(cost)
for i in range(V - 1):
    for j in range(i + 1, V):
        g = dijkstra_back(i, j)
        # print(i, j, g)
        for k in range(len(g) - 1):
            cost2[g[k]][g[k + 1]] = INF
            cost2[g[k + 1]][g[k]] = INF
            
cnt = 0
for i in range(V):
    for j in range(V):
        if cost2[i][j] != INF:
            cnt += 1
                     
print(cnt // 2)

Fixed submission:
import copy
from scipy.sparse.csgraph import floyd_warshall as wf

N, M = map(int, input().split())
INF = float('inf')

d = [[INF] * (N) for i in range(N)]
e_list = []
for i in range(N):
    d[i][i] = 0
for _ in range(M):
    a, b, c = map(int, input().split())
    d[a - 1][b - 1] = c
    d[b - 1][a - 1] = c
    e_list.append([a - 1, b - 1, c])
    
wf = wf(d)

cnt = M
for a, b, c in e_list:
    for i in range(N):
        if wf[i][a] + c == wf[i][b]:
            cnt -= 1
            break
    
print(cnt)

Buggy python submission (verdict: Runtime Error):
import heapq
import copy

V, M = map(int, input().split())
d = [0] * V
prev = [0] * V

cost = [[INF] * V for i in range(V)]
for i in range(M):
    a, b, c = map(int,  input().split())
    cost[a - 1][b - 1] = c
    cost[b - 1][a - 1] = c
    
def dijkstra_back(s, t):
    for i in range(V):
        prev[i] = s
        d[i] = float('inf')
    d[s] = 0
    h = []
    heapq.heappush(h, [0, s])
    
    while h != []:
        p = heapq.heappop(h)
        v = p[1]
        if d[v] < p[0]:
            continue
         
        for i in range(V):
            if d[i] > d[v] + cost[v][i]: 
                d[i] = d[v] + cost[v][i]
                heapq.heappush(h, [d[i], i])
                prev[i] = v
        
    path = [t]
    while prev[t] != s:
        path.append(prev[t])
        prev[t] = prev[prev[t]]
    path.append(s)
    path = path[::-1]
    return path

cost2 = copy.deepcopy(cost)
for i in range(V - 1):
    for j in range(i + 1, V):
        g = dijkstra_back(i, j)
        # print(i, j, g)
        for k in range(len(g) - 1):
            cost2[g[k]][g[k + 1]] = INF
            cost2[g[k + 1]][g[k]] = INF
            
cnt = 0
for i in range(V):
    for j in range(V):
        if cost2[i][j] != INF:
            cnt += 1
                     
print(cnt // 2)

Fixed submission:
import copy
from scipy.sparse.csgraph import floyd_warshall as wf

N, M = map(int, input().split())
INF = float('inf')

d = [[INF] * (N) for i in range(N)]
e_list = []
for i in range(N):
    d[i][i] = 0
for _ in range(M):
    a, b, c = map(int, input().split())
    d[a - 1][b - 1] = c
    d[b - 1][a - 1] = c
    e_list.append([a - 1, b - 1, c])
    
wf = wf(d)

cnt = M
for a, b, c in e_list:
    for i in range(N):
        if wf[i][a] + c == wf[i][b]:
            cnt -= 1
            break
    
print(cnt)

Buggy python submission (verdict: Runtime Error):
import heapq
import copy

V, M = map(int, input().split())
d = [0] * V
prev = [0] * V

cost = [[INF] * V for i in range(V)]
for i in range(M):
    a, b, c = map(int,  input().split())
    cost[a - 1][b - 1] = c
    cost[b - 1][a - 1] = c
    
def dijkstra_back(s, t):
    for i in range(V):
        prev[i] = s
        d[i] = float('inf')
    d[s] = 0
    h = []
    heapq.heappush(h, [0, s])
    
    while h != []:
        p = heapq.heappop(h)
        v = p[1]
        if d[v] < p[0]:
            continue
         
        for i in range(V):
            if d[i] > d[v] + cost[v][i]: 
                d[i] = d[v] + cost[v][i]
                heapq.heappush(h, [d[i], i])
                prev[i] = v
        
    path = [t]
    while prev[t] != s:
        path.append(prev[t])
        prev[t] = prev[prev[t]]
    path.append(s)
    path = path[::-1]
    return path

cost2 = copy.deepcopy(cost)
for i in range(V - 1):
    for j in range(i + 1, V):
        g = dijkstra_back(i, j)
        # print(i, j, g)
        for k in range(len(g) - 1):
            cost2[g[k]][g[k + 1]] = INF
            cost2[g[k + 1]][g[k]] = INF
            
cnt = 0
for i in range(V):
    for j in range(V):
        if cost2[i][j] != INF:
            cnt += 1
                     
print(cnt // 2)

Fixed submission:
import copy
from scipy.sparse.csgraph import floyd_warshall as wf

N, M = map(int, input().split())
INF = float('inf')

d = [[INF] * (N) for i in range(N)]
e_list = []
for i in range(N):
    d[i][i] = 0
for _ in range(M):
    a, b, c = map(int, input().split())
    d[a - 1][b - 1] = c
    d[b - 1][a - 1] = c
    e_list.append([a - 1, b - 1, c])
    
wf = wf(d)

cnt = M
for a, b, c in e_list:
    for i in range(N):
        if wf[i][a] + c == wf[i][b]:
            cnt -= 1
            break
    
print(cnt)

Buggy python submission (verdict: Time Limit Exceeded):
import copy

V, M = map(int, input().split())
d = [0] * V
prev = [0] * V
INF = float('inf')

cost = [[INF] * V for i in range(V)]
for i in range(M):
    a, b, c = map(int,  input().split())
    cost[a - 1][b - 1] = c
    cost[b - 1][a - 1] = c
    
def dijkstra_back(s,t):
    prev = [s] * V
    d = [float("inf")] * V
    used = [False] * V
    d[s] = 0
    
    while True:
        v = -1
        for i in range(V):
            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
        
        for i in range(V):
            if d[i] > d[v] + cost[v][i]: 
                d[i] = d[v] + cost[v][i]
                prev[i] = v
        
    path = [t]
    while prev[t] != s:
        path.append(prev[t])
        prev[t] = prev[prev[t]]
    path.append(s)
    path = path[::-1]
    return path

cost2 = copy.deepcopy(cost)
for i in range(V - 1):
    for j in range(i + 1, V):
        g = dijkstra_back(i, j)
        for k in range(len(g) - 1):
            cost2[g[k]][g[k + 1]] = INF
            cost2[g[k + 1]][g[k]] = INF
            
cnt = 0
for i in range(V):
    for j in range(V):
        if cost2[i][j] != INF:
            cnt += 1
                     
print(cnt // 2)

Fixed submission:
import copy
from scipy.sparse.csgraph import floyd_warshall as wf

N, M = map(int, input().split())
INF = float('inf')

d = [[INF] * (N) for i in range(N)]
e_list = []
for i in range(N):
    d[i][i] = 0
for _ in range(M):
    a, b, c = map(int, input().split())
    d[a - 1][b - 1] = c
    d[b - 1][a - 1] = c
    e_list.append([a - 1, b - 1, c])
    
wf = wf(d)

cnt = M
for a, b, c in e_list:
    for i in range(N):
        if wf[i][a] + c == wf[i][b]:
            cnt -= 1
            break
    
print(cnt)