Go: package main

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

func getScanner(fp *os.File) *bufio.Scanner {
	scanner := bufio.NewScanner(fp)
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 500001), 500000)
	return scanner
}

func getNextString(scanner *bufio.Scanner) string {
	scanner.Scan()
	return scanner.Text()
}

func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}

func main() {
	fp := os.Stdin
	if len(os.Args) > 1 {
		fp, _ = os.Open(os.Args[1])
	}

	scanner := getScanner(fp)
	writer := bufio.NewWriter(os.Stdout)

	n := getNextInt(scanner)

	g := makeGraph(n)
	for i := 0; i < n; i++ {
		u := getNextInt(scanner)
		k := getNextInt(scanner)
		for ii := 0; ii < k; ii++ {
			v := getNextInt(scanner)
			c := getNextInt(scanner)
			g[u][v] = c
		}
	}

	ans := make([]int, n)
	im := make(IntMap, 1)
	im.increment(0)
	for len(im) < n {
		min := 1 << 30
		x := -1
		for u := range im {
			for v := 0; v < n; v++ {
				if im.get(v) != 0 {
					continue
				}
				if min > ans[u]+g[u][v] {
					min = ans[u] + g[u][v]
					x = v
				}
			}
		}
		im.increment(x)
		ans[x] = min
	}

	for i := 0; i < n; i++ {
		fmt.Fprintln(writer, fmt.Sprintf("%d %d", i, ans[i]))
	}
	writer.Flush()
}

func makeGraph(n int) [][]int {
	g := make([][]int, n)
	for i := 0; i < n; i++ {
		g[i] = make([]int, n)
		for ii := 0; ii < n; ii++ {
			g[i][ii] = 1 << 30
		}
	}

	return g
}

// IntMap ...
type IntMap map[int]int

func (m IntMap) get(key int) int {
	if _, ok := m[key]; ok {
		return m[key]
	}
	return 0
}
func (m IntMap) increment(key int) {
	if _, ok := m[key]; ok == false {
		m[key] = 0
	}
	m[key]++
}

Python: # ALDS1_12_V Single Source Shortest Path I
import sys

n = int(input())
G = [[float('inf')] * n for _ in range(n)]
for i in range(n):
    ukvc = list(map(int, sys.stdin.readline().strip().split()))
    u = ukvc[0]
    k = ukvc[1]

    for j in range(k):
        G[u][ukvc[2 + 2 * j]] = ukvc[3 + 2 * j]

p = [n] * n  # 親を保存するリスト　親ノードとしてあり得ない n を初期リストとする
c = ['white'] * n # 最小経路木への接続チェック　white 未接続　black 接続済
d = [float('inf')] * n  # ノード i までの最小経路を保存するリスト
d[0] = 0  # 根への距離は0とする
p[0] = -1  # 根の親は -1 とする
u = 0  # 次のループで最小経路木につなげるノード

while 'white' in c:
    c[u] = 'black'

    v = None
    minpath = float('inf')
    for i in range(n):
        d[i] = min(d[i], d[u] + G[u][i])
        if (d[i] < minpath) & (c[i] == 'white'):
            minpath = d[i]
            v = i
            p[i] = u

    if v is None:
        break

    u = v

for i in range(n):
    print('{} {}'.format(i, d[i]))

Python: def dijkstra(n,s):
    inf=float("inf")
    color=["white" for i in range(n)]
    D=[inf for i in range(n)]
    P=[0 for i in range(n)]
    M=[[inf for i in range(n)] for j in range(n)]

    for i in range(n):
        weight=list(map(int,input().split()))[2:]
        for j in range(len(weight)//2):
            M[i][weight[2*j]]=weight[2*j+1]

    D[s]=0
    P[s]=-1

    while 1:
        cost,u=inf,0
        for i in range(n):
            if color[i]!="black" and D[i]<cost:
                cost=D[i]
                u=i

        if cost==inf:break

        color[u]="black"

        for i in range(n):
            if color[i]!="black" and M[u][i]!=inf:
                if D[u]+M[u][i]<D[i]:
                    D[i]=D[u]+M[u][i]
                    color[i]="gray"
                    P[i]=u

    return D


n=int(input())
distant=dijkstra(n,0)
for i in range(n):
    print(i,distant[i])

Python: def dijkstra():
    d[0] = 0
    color[0] = GRAY

    while True:
        minv = INF
        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 i in range(N):
            if color[i] != BLACK and M[u][i] != INF:
                if d[i] > d[u] + M[u][i]:
                    d[i] = d[u] + M[u][i]
                    color[i] = GRAY

INF = 10 ** 18
WHITH = 0
GRAY = 1
BLACK = 2
N = int(input())
M = [[INF for _ in range(N)] for _ in range(N)]
d = [INF] * N
color = [WHITH] * N

for i in range(N):
    lst = list(map(int, input().split()))
    for j in range(lst[1]):
        M[lst[0]][lst[2 + (j * 2)]] = lst[3 + (j * 2)]

dijkstra()
for i in range(N):
    v = d[i]
    if v == INF:
        v = -1
    print(i, v)

Python: #!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# FileName: 	single_source_shortest_path
# CreatedDate:  2020-06-08 21:54:58 +0900
# LastModified: 2020-06-08 22:28:47 +0900
#


import os
import sys
from collections import deque
#import numpy as np
#import pandas as pd


def main():
    n = int(input())
    graph = [[] for _ in range(n)]
    for _ in range(n):
        line = list(map(int,input().split()))
        u,k = line[0],line[1]
        path = line[2:]
        for i in range(0,2*k,2):
            graph[u].append([path[i+1],path[i]])
    
#    print(graph)
    s=0
    distance=[-1]*n
    Q = deque([s])
    distance[0]=0
    

    while Q:
        u = Q.popleft()
        for dis,v in graph[u]:
            if distance[v]==-1:
                distance[v]=distance[u]+dis
                Q.append(v)

            if distance[v]>distance[u]+dis:
                distance[v]=distance[u]+dis
                Q.append(v)
            


    for i,dis in enumerate(distance):
        print(i,dis)


if __name__ == "__main__":
    main()

Python: INF = 100000 * 100

def dijkstra(s: int) -> None:
	d[s] = 0	
	while True:
		mincost = INF
		for i in range(n):
			if color[i] != "BLACK" and d[i] < mincost:
				mincost = d[i]
				u = i
		if mincost == INF:
			break
		color[u] = "BLACK"
		for v in range(n):
			if color[v] != "BLACK" and M[u][v] != None:
				if d[u] + M[u][v] < d[v]:
					d[v] = d[u] + M[u][v]
					pi[v] = u
					color[v] = "GRAY"


if __name__ == "__main__":
	n = int(input())
	G = []
	M = [[None for _ in range(n)] for _ in range(n)]
	color = ["WHITE" for _ in range(n)]
	d = [INF for _ in range(n)]
	pi = [None for _ in range(n)]

	for _ in range(n):
		l = list(map(int, input().split()))
		u = l[0]
		k = l[1]
		for i in range(k):
			v = l[2 * (i + 1)]
			c = l[2 * (i + 1) + 1]
			M[u][v] = c
	dijkstra(0)
	for v in range(n):
		print(f"{v} {d[v]}")

Python: import sys

def dijkstra(v_count: int, edges: list, start: int,
             *, adj_matrix: bool = False, unreachable=float("inf")) -> list:
    """ ダイクストラ法
    :param v_count: 頂点数
    :param edges: 辺のリスト(隣接リストor隣接行列)
    :param start: スタートする頂点
    :param adj_matrix: edgesに渡したリストが隣接行列ならTrue
    :param unreachable: 到達不能を表すコスト値
                        隣接行列の辺の有無の判定および返すリストの初期値に使用
    """
    from heapq import heappush, heappop

    vertices = [unreachable] * v_count
    vertices[start] = 0
    q, rem = [(0, start)], v_count - 1

    while q and rem:
        cost, v = heappop(q)
        if vertices[v] < cost:
            continue
        rem -= 1

        dests = (filter(lambda x: x[1] != unreachable, enumerate(edges[v]))
                 if adj_matrix else edges[v])

        for dest, _cost in dests:
            newcost = cost + _cost
            if vertices[dest] > newcost:
                vertices[dest] = newcost
                heappush(q, (newcost, dest))

    return vertices

n = int(input())
inf = float("inf")
edges = [[inf]*n for _ in [0]*n]
for a in (tuple(map(int, l.split())) for l in sys.stdin):
    _from = a[0]
    for to, cost in zip(a[2::2], a[3::2]):
        edges[_from][to] = cost
vertices = dijkstra(n, edges, 0, adj_matrix=True)
for i, n in enumerate(vertices):
    print(i, n)