import os
import sys
from io import BytesIO, IOBase
# region fastio
BUFSIZE = 8192
class FastIO(IOBase):
    def __init__(self, file):
        self.newlines = 0
        self._fd = file.fileno()
        self.buffer = BytesIO()
        self.writable = "x" in file.mode or "r" not in file.mode
        self.write = self.buffer.write if self.writable else None
 
    def read(self):
        while True:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            if not b:
                break
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines = 0
        return self.buffer.read()
 
    def readline(self):
        while self.newlines == 0:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            self.newlines = b.count(b"\n") + (not b)
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines -= 1
        return self.buffer.readline()
 
    def flush(self):
        if self.writable:
            os.write(self._fd, self.buffer.getvalue())
            self.buffer.truncate(0), self.buffer.seek(0)
 
 
class IOWrapper(IOBase):
    def __init__(self, file):
        self.buffer = FastIO(file)
        self.flush = self.buffer.flush
        self.writable = self.buffer.writable
        self.write = lambda s: self.buffer.write(s.encode("ascii"))
        self.read = lambda: self.buffer.read().decode("ascii")
        self.readline = lambda: self.buffer.readline().decode("ascii")
 
 
sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
input = lambda: sys.stdin.readline()
 
# --------------------------------------------------------------------

def RL(): return map(int, sys.stdin.readline().split())
def RLL(): return list(map(int, sys.stdin.readline().split()))
def N(): return int(input())
def S(): return input().strip()
def print_list(l): print(' '.join(map(str, l)))
    
# sys.setrecursionlimit(100000)
# import random
# from functools import reduce
# from functools import lru_cache
# from heapq import *
# from collections import deque as dq
# from math import gcd
# import bisect as bs
# from collections import Counter
# from collections import defaultdict as dc 

for tt in range(N()):        
    n, m, k = RL()
    if tt == 48: print(n, m, k)    
    dic = [[] for _ in range(n + 1)]
    p1 = 0
    p2 = float('inf')
    edges = []
    for _ in range(m):
        u, v, t = RL()
        if tt == 48: print(u, v, t)
        if t <= k:
            if t > p1: p1 = t 
            dic[u].append(v)
            dic[v].append(u)
        else:
            if t < p2: p2 = t
            edges.append((u, v, t))
    root = [0] * (n + 1)
    region_count = 0
    for r in range(1, n + 1):
        if root[r]: continue
        region_count += 1
        now = [r]
        root[r] = r
        while now:
            node = now.pop()
            for nex in dic[node]:
                if root[nex] == 0:
                    root[nex] = r 
                    now.append(nex)
    if region_count == 1:
        print(min(p2 - k, k - p1))
    else:
        dic = {}
        for u, v, t in edges:
            if root[u] == root[v]: continue
            a, b = root[u], root[v]
            if a > b: 
                a, b = b, a
            if (a, b) not in dic:
                dic[(a, b)] = t 
            else:
                dic[(a, b)] = min(dic[(a, b)], t)
        s = sorted(list(dic.values()))
        print(sum(s[:region_count - 1]) - k * (region_count - 1))

