import heapq
import sys

input = sys.stdin.readline

def solve() :
    N, M = map(int, input().split())
    
    graph = [[] for _ in range(N+1)]
    
    for _ in range(M) :
        A, B, C = map(int, input().split())
        graph[A].append((B, C))
        graph[B].append((A, C))

    pq = []
    visited = [False] * (N+1)
    heapq.heappush(pq, (0,1))
    count = 0
    totalCost = 0
    maxCost = 0
    
    while pq :
        cost, node = heapq.heappop(pq)
        
        if visited[node] : continue
        
        visited[node] = True
        count += 1
        totalCost += cost
        maxCost = max(cost, maxCost)
        
        if count == N : break
        
        for next, n_cost in graph[node] :
            if not visited[next] :
                heapq.heappush(pq, (n_cost, next))
        
    print(totalCost-maxCost)

solve()