Problem: There are N people standing on the x-axis. Let the coordinate of Person i be x_i. For every i, x_i is an integer between 0 and 10^9 (inclusive). It is possible that more than one person is standing at the same coordinate.  You will given M pieces of information regarding the positions of these people. The i-th piece of information has the form (L_i, R_i, D_i). This means that Person R_i is to the right of Person L_i by D_i units of distance, that is, x_{R_i} - x_{L_i} = D_i holds.  It turns out that some of these M pieces of information may be incorrect. Determine if there exists a set of values (x_1, x_2, ..., x_N) that is consistent with the given pieces of information.

Submission attempts (in order):
N,M = map(int,input().split())
Adj_list = defaultdict(set)

for i in range(M):
    a, b, c = map(int, input().split())
    Adj_list[a-1].add((b-1, c))
    Adj_list[b-1].add((a-1, -c))
visited =[None]*(N)
ok = True
stack = []
for x in range(N):
   if visited[x] is not None:continue
   visited[x] = 0
   stack = [x]
   while stack:
       v = stack.pop()
       for to,d in Adj_list[v]:
           if visited[to] is None:
               visited[to] = G[v] + d
               stack.append(to)
           else:
               if G[to] != G[v]+d:
                   ok = False
                   break
   if ok == False:
        break
print("Yes" if ok else "No")

N,M = map(int,input().split())
Adj_list = [[] for _ in range(N) ]

for i in range(M):
    a, b, c = map(int, input().split())
    Adj_list[a-1].add((b-1, c))
    Adj_list[b-1].add((a-1, -c))
visited =[None]*(N)
ok = True
stack = []
for x in range(N):
   if visited[x] is not None:continue
   visited[x] = 0
   stack = [x]
   while stack:
       v = stack.pop()
       for to,d in Adj_list[v]:
           if visited[to] is None:
               visited[to] = G[v] + d
               stack.append(to)
           else:
               if G[to] != G[v]+d:
                   ok = False
                   break
   if ok == False:
        break
print("Yes" if ok else "No")

import itertools
import math
from collections import deque
from collections import defaultdict
from itertools import permutations
import heapq
import bisect
from scipy.sparse.csgraph import floyd_warshall as wf
INF = float("inf")


N,M = map(int,input().split())
Adj_list = defaultdict(set)

for i in range(M):
    a, b, c = map(int, input().split())
    Adj_list[a-1].add((b-1, c))
    Adj_list[b-1].add((a-1, -c))
visited =[None]*(N)
ok = True
stack = []
for x in range(N):
   if visited[x] is not None:continue
   visited[x] = 0
   stack = [x]
   while stack:
       v = stack.pop()
       for to,d in Adj_list[v]:
           if visited[to] is None:
               visited[to] = G[v] + d
               stack.append(to)
           else:
               if G[to] != G[v]+d:
                   ok = False
                   break
   if ok == False:
        break
print("Yes" if ok else "No")


import itertools
import math
from collections import deque
from collections import defaultdict
from itertools import permutations
import heapq
import bisect
from scipy.sparse.csgraph import floyd_warshall as wf
INF = float("inf")


N,M = map(int,input().split())
Adj_list = defaultdict(set)

for i in range(M):
    a, b, c = map(int, input().split())
    Adj_list[a-1].add((b-1, c))
    Adj_list[b-1].add((a-1, -c))
visited =[None]*(N)
ok = True
stack = []
for x in range(N):
   if visited[x] is not None:continue
   visited[x] = 0
   stack = [x]
   while stack:
       v = stack.pop()
       for to,d in Adj_list[v]:
           if visited[to] is None:
               visited[to] = visited[v] + d
               stack.append(to)
           else:
               if visited[to] != visited[v]+d:
                   ok = False
                   break
   if ok == False:
        break
print("Yes" if ok else "No")

Verdicts: Runtime Error

Runtime Error

Runtime Error

Accepted