Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

const (
	MAX_N      = 200
	MAX_WEIGHT = 2000
)

type Edge struct {
	start  int
	end    int
	weight int
}

type ShortestInfo struct {
	edges    []Edge
	shortest int
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	n, err := nextInt(sc)
	if err != nil {
		panic(err)
	}

	shortestList := make([]ShortestInfo, n)
	for i := 1; i < n; i++ {
		shortestList[i] = ShortestInfo{edges: []Edge{}, shortest: MAX_N*MAX_WEIGHT + 1}
	}

	adjacentMatrix := make([][]int, n)
	for i := 0; i < n; i++ {
		adjacentMatrix[i] = make([]int, n)
		for j := 0; j < n; j++ {
			v, err := nextInt(sc)
			if err != nil {
				panic(err)
			}
			adjacentMatrix[i][j] = v
		}
	}

	mst([]int{1}, shortestList, adjacentMatrix)
	fmt.Println(calculateMinWeight(shortestList))
}

func calculateMinWeight(shortestList []ShortestInfo) int {
	visitedList := make([]bool, len(shortestList))
	visitedList[0] = true
	sumWeight := 0
	for !visitedAll(visitedList) {
		shortestInfo := shortestList[0]
		shortestList = shortestList[1:]
		edges := shortestInfo.edges
		for _, edge := range edges {
			if !visitedList[edge.end-1] {
				visitedList[edge.end-1] = true
				sumWeight += edge.weight
			}
		}
	}
	return sumWeight
}

func visitedAll(visitedList []bool) bool {
	for _, v := range visitedList {
		if !v {
			return false
		}
	}
	return true
}

func mst(nodeStack []int, shortestList []ShortestInfo, adjacentMatrix [][]int) {
	for len(nodeStack) > 0 {
		currentNode := nodeStack[0]
		nodeStack = nodeStack[1:]
		currentShortest := getShortest(currentNode, shortestList)
		adjacents := findAdjacents(currentNode, adjacentMatrix)
		for i := 0; i < len(adjacents); i++ {
			adj := adjacents[i]
			s := getShortest(adj.end, shortestList)
			if currentShortest.shortest+adj.weight < s.shortest || (currentShortest.shortest+adj.weight == s.shortest && len(currentShortest.edges)+1 > len(s.edges)) {
				setShortest(adj.end, adj, currentShortest, shortestList)
				nodeStack = append(nodeStack, adj.end)
			}
		}
	}
}

func getShortest(node int, shortestList []ShortestInfo) ShortestInfo {
	return shortestList[node-1]
}

func setShortest(node int, edge Edge, currentShortest ShortestInfo, shortestList []ShortestInfo) {
	newEdges := make([]Edge, len(currentShortest.edges)+1)
	for i := 0; i < len(newEdges)-1; i++ {
		newEdges[i] = currentShortest.edges[i]
	}
	newEdges[len(newEdges)-1] = edge
	shortestInfo := ShortestInfo{edges: newEdges, shortest: currentShortest.shortest + edge.weight}
	shortestList[node-1] = shortestInfo
}

func findAdjacents(currentNode int, adjacentMatrix [][]int) []Edge {
	adjacents := adjacentMatrix[currentNode-1]
	edges := []Edge{}
	for i, v := range adjacents {
		if v > 0 {
			edges = append(edges, Edge{start: currentNode, end: i + 1, weight: v})
		}
	}
	return edges
}

func nextInt(sc *bufio.Scanner) (int, error) {
	sc.Scan()
	return strconv.Atoi(sc.Text())
}

Python: n=int(input())
# m=[list(map(int,input().split()))for _ in[0]*n]
m = [[-1 for i in range(n)] for j in range(n)]
for i in range(n): #隣接の辺のコストを入力
  nums = list(map(int, input().split()))
  for j in range(n):
    m[i][j] = nums[j]

d=[0]+[10**9]*n
b=[1]*n
a=0
while 1:
  u=-1
  for i in range(n):
    if b[i] and (u<0 or d[i]<d[u]):
      u=i
  if u<0:
    break
  b[u]=0
  a+=d[u]
  for v in range(n):
    t=m[u][v]
    if t+1 and d[v]>t:
      d[v]=t
print(a)

Python: N = 100

n = int(input())
adj = [[0 for i in range(n)] for j in range(n)]

for i in range(n):
    tmp = list(map(int, input().split()))
    u = tmp[0]
    u = u -1
    k = tmp[1]
    v = tmp[2:]
    for j in range(k):
        adj[u][v[j]-1] = 1

for i in range(n):
    for j in range(n):
        print(adj[i][j], end=" ")
    print()

Python: # 最小全域木 Minumum spannin tree

MAX_EDGE_COST = 2001
n = int(input())
A = [[0 for i in range(n)] for i in range(n)]
for i in range(n):
    A[i] = [int(i) for i in input().split()]

col = [-1 for i in range(n)]
d = [MAX_EDGE_COST for i in range(n)]
p = [-1 for i in range(n)]

d[0] = 0
while True:
    mincost = MAX_EDGE_COST;
    for i in range(n):
        if col[i] != 1 and d[i] < mincost:
            mincost = d[i]
            u = i
    
    if mincost == MAX_EDGE_COST:
        break;
    
    col[u] = 1
    
    for v in range(n):
        if col[v] != 1 and A[u][v] != -1:
            if A[u][v] < d[v]:
                d[v] = A[u][v]
                p[v] = u
                col[v] = 0

sum = 0
for i in range(n):
    if p[i] != -1:
        sum += A[i][p[i]]

print(sum)

Python: MAX = 100
INFTY = 1 << 21
WHITE = 0
GRAY = 1
BLACK = 2
d = [INFTY for i in range(n)]
p = [-1 for i in range(n)]
color = [WHITE for i in range(n)]

n = int(input())
M = [[map(int, input().split()) for i in range(n)] for j in range(n)]
for i in range(n):
    for j in range(n):
        if (M[i][j] == -1):
            M[i][j] = INFTY

def prim():
    global M, d, p, color
    d[0] = 0
    while(1):
        minv = INFTY
        u = -1
        for i in range(n):
            if (minv > d[i] and color[i] != BLACK):
                u = i
                minv = d[i]
        if (u == -1):
            break
        color[u] = BLACK
        for v in range(n):
            if (color[v] != BLACK and M[u][v] != INFTY):
                if (d[v] > M[u][v]):
                    d[v] = M[u][v]
                    p[v] = u
                    color[v] = GRAY
    
    return sum([M[i][p[i]] for i in range(n) if (p[i] != -1)])

print(prim())

Python: n = int(input())
a = []

for i in range(n):
    inp = input()
    if "-1" in inp:
        inp = inp.replace("-1","10000")
    a.append(list(map(int, inp.split())))

w = 0
v = set(range(1,n))

edge    = [ 0, 0]
min_w   = [-1,-1]
min_idx = [-1,-1]

while v:
    min_w[0] = min(a[edge[0]])
    min_w[1] = min(a[edge[1]])
    min_idx[0] = a[edge[0]].index(min_w[0])
    min_idx[1] = a[edge[1]].index(min_w[1])
    if min_w[0] <= min_w[1]:
        k = 0
    else:
        k = 1
    if min_idx[k] not in v:
        a[edge[k]][min_idx[k]] = 10000
        continue
    else:
        w += min_w[k]
        v.remove(min_idx[k])
        edge[k] = min_idx[k]

print(w)

Python: class Node(object):
    def __init__(self, V):
        self.V = V
        self.d = float('inf')
        self.p = -1
        self.state = -1
        # -1 -> undiscovered
        #  1 -> finished
        #  0 -> found(not finished)


M = [float('inf')] * 100
for i in range(100):
    M[i] = [float('inf')] * 100

n = int(input())
nodes = [0] * 100
for i in range(n):
    V = [int(x) for x in input().split()] 
    for (j,m) in enumerate(V):
        M[i][j] = m if not m == -1 else float('inf') 
    nodes[i] = Node([])

nodes[0].d = 0
while True:
    mincost = float('inf')
    u = -1
    for i in range(n):
        node = nodes[i]
        if (mincost > node.d) and (node.state != 1):
            u = i
            mincost = node.d

    if u == -1:
        break

    nodes[u].state = 1
    for v in range(n):
        node = nodes[v]
        if (node.state != 1) and (M[u][v] != float('inf')):
            if node.d > M[u][v]:
                node.d = M[u][v]
                node.p = u
                node.state = 0

sum = 0
for i in range(n):
    if nodes[i].p != -1:
        sum += M[i][nodes[i].p]

print(sum)

Python: def prim(cost):
 res = 0
 V = len(cost)
 mincost = [float("inf")] * V
 used = [False] * V
 mincost[0] = 0
 while True:
  v = -1
  for u in range(V):
   if not used[u] and \
    (v == -1 or mincost[u] < mincost[v]):
    v = u
  if v == -1: break
  used[v] = True
  res += mincost[v]
  for u in range(V):
    if cost[v][u] == -1: continue
    mincost[u] = min(mincost[u], cost[v][u])
 return res