Go: package main

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

const (
	white int = iota
	gray
	black
)

type node struct {
	id     int
	parent int
	edge   []int
	weight []int
	color  int
}

type graph struct {
	nodes    []node
	distance []int
}

var infty = 1 << 32
var null = -1

func constructgraph() *graph {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	n := nextInt(sc)

	g := &graph{make([]node, n), make([]int, n)}

	for i := 0; i < n; i++ {
		id := nextInt(sc)
		edges := nextInt(sc)
		n := node{}
		n.id = id
		n.edge = make([]int, edges)
		n.weight = make([]int, edges)
		n.color = white
		for j := 0; j < edges; j++ {
			to := nextInt(sc)
			w := nextInt(sc)
			n.edge[j] = to
			n.weight[j] = w
		}
		g.nodes[id] = n
	}
	return g
}

func nextInt(sc *bufio.Scanner) int {
	sc.Scan()
	v, _ := strconv.Atoi(sc.Text())
	return v
}

func (g *graph) preparedijkstra(s int) {
	for i := 0; i < len(g.nodes); i++ {
		g.nodes[i].color = white
		g.nodes[i].parent = null
		g.distance[i] = infty
	}
	g.distance[s] = 0
}

func (g *graph) dijkstra(s int) []int {
	g.preparedijkstra(s)

	for {
		var u int
		mincost := infty
		for i, d := range g.distance {
			if g.nodes[i].color != black && mincost > d {
				mincost = d
				u = i
			}
		}

		if mincost == infty {
			break
		}

		g.nodes[u].color = black

		for i, e := range g.nodes[u].edge {
			if g.nodes[e].color != black {
				if g.distance[e] > g.distance[u]+g.nodes[u].weight[i] {
					g.distance[e] = g.distance[u] + g.nodes[u].weight[i]
					g.nodes[e].parent = u
					g.nodes[e].color = gray
				}
			}
		}
	}
	return g.distance
}

func printShortestPath(d []int) {
	for i, v := range d {
		fmt.Printf("%d %d\n", i, v)
	}
}

func main() {
	g := constructgraph()
	d := g.dijkstra(0)
	printShortestPath(d)
}

Python: INF = float('inf')


def dijkstra(source):
    distance[source] = 0
    parent[source] = -1

    while True:
        mincost = INF
        for i in range(n):
            if color[i] != 'black' and distance[i] < mincost:
                mincost = distance[i]
                u = i

        if mincost == INF:
            break

        color[u] = 'black'

        for v in range(n):
            if color[v] != 'black' and adjMat[u][v] != INF:
                if distance[u] + adjMat[u][v] < distance[v]:
                    distance[v] = distance[u] + adjMat[u][v]
                    parent[v] = u
                    color[v] = 'gray'


n = int(input())
color = ['white'] * n
parent = [-1] * n
distance = [INF] * n

adjMat = [[INF] * n for _ in range(n)]
for i in range(n):
    inputList = list(map(int, input().split()))
    adjRow = inputList[0::2][1:]
    weightRow = inputList[1::2][1:]
    for v, weight in zip(adjRow, weightRow):
        adjMat[i][v] = weight

dijkstra(0)

for index, distance in enumerate(distance):
    print(('{} {}').format(index, distance))

Python: import sys
input = sys.stdin.readline

INF = 10**9
WHITE = -100
GRAY = -1000
BLACK = -10000

def main():
	m = int(input().strip())
	s = [[-1] * m for _ in range(m)]
	for i in range(m):
		l = list(map(int, input().strip().split()))
		for j in range(l[1]):
			s[i][l[2 + 2 * j]] = l[3 + 2 * j]
	color = [WHITE] * m
	d = [INF] * m
	p = [-1] * m

	d[0] = 0
	# for i in range(m):
	# 	print(s[i])
	color[0] = BLACK
	u = 0
	while True:
		for i in range(m):
			if color[i] != BLACK and s[u][i] != -1:
				if d[u] + s[u][i] < d[i]:
					d[i] = d[u] + s[u][i]
					p[i] = u
		mincost = INF
		for i in range(m):
			if color[i] != BLACK and d[i] < mincost:
				mincost = d[i]
				u = i
		if mincost == INF:
			break
		color[u] = BLACK
	for i in range(m):
		print("{} {}".format(i, d[i]))


if __name__ == '__main__':
	main()

Python: def diikstraMethd(G, s):
    # ?????????
    n = len(G)
    # White:0 Gyay:1 Black:2
    color = [0 for _ in range(n)]
    d = [INF for _ in range(n)]
    p = [None for _ in range(n)]

    d[s] = 0

    while True:
        mincost = INF
        for i in range(n):
            if color[i] != 2 and d[i] < mincost:
                mincost = d[i]
                u = i

        if mincost == INF: break

        color[u] = 2

        for v in range(n):
            if color[v] != 2 and M[u][v] != INF:
                if d[u] + M[u][v] < d[v]:
                    d[v] = d[u] + M[u][v]
                    p[v] = u
                    color[u] = 1

    return d

if __name__ == '__main__':
    n = int(input())
    M = [[INF for _ in range(n)] for i in range(n)]
    for _ in range(n):
        tmp = list(map(int, input().split()))
        u = tmp.pop(0)
        k = tmp.pop(0)
        for _ in range(k):
            v = tmp.pop(0)
            c = tmp.pop(0)
            M[u][v] = c
    d = diikstraMethd(M, 0)

    for i in range(n):
        print('{0} {1}'.format(i, d[i]))

Python: from __future__ import division, print_function
from sys import stdin, maxint
 
 
def main():
    num = int(stdin.readline())
 
    y = []
    for _ in xrange(num):
        it = iter(int(s) for s in stdin.readline().split()[1:])
        y.append([(next(it), next(it)) for _ in xrange(next(it))])
 
    weight = [maxint] * num
    weight[0] = 0
    t = set(xrange(1, num))
    index = 0
 
    while t:
        for v, cost in y[index]:
            if v not in t:
                continue
            weight[v] = min(weight[v], cost + weight[index])
 
        index = min(t, key=lambda i: weight[i])
        t.remove(index)
 
    for i, d in enumerate(weight):
        print(i, d)
 
 
main()

Python: # coding: utf-8
# Your code here!

WHITE = 0
GRAY = 1
BLACK = 2

INF = 2000000000

def dijkstra(s):
    while True:
        u = 0
        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[i][v] != -1:
                if d[u] + m[u][v] < d[v]:
                    d[v] = d[u] + m[u][v]
                    p[v] = u
                    color[v] = GRAY

n = int(input())

m = [[INF for i in range(n)] for j in range(n)]
for i in range(n):
    nums=list(map(int,input().split()))
    for j in range(nums[1]):
        m[i][nums[2*j+2]] = nums[2*j+3]

color = [WHITE] * n
d = [INF] * n 
d[0] = 0
p = [-1] * n

dijkstra(0)
for v in range(n):
    print(v, d[v])

Python: # -*- coding: utf-8 -*-
"""
Created on Sat Jul 14 19:11:44 2018

@author: maezawa
"""
infinity = 2*10**9

n = int(input())
adj = [[] for _ in range(n)]

for j in range(n):
    ain = list(map(int, input().split()))
    u = ain[0]
    k = ain[1]
    for i in range(2,2+2*k,2):
        adj[u].append([ain[i],ain[i+1]])
    #print(*adj[u])

color = [0]*n
d = [infinity for _ in range(n)]
p = [0]*n
p[0] = -1
d[0] = 0

def dyk(s):
    cnt = 1
    cur = s
    candidates = set() # remaining nodes
    while True:
        for i, w in adj[cur]:
            if color[i] == 2:
                continue
            if d[i] > d[cur] + w:
                d[i] = d[cur] + w
                color[i] = 1
            candidates.add(i)
        min_d = infinity
        for j in candidates:
            if min_d > d[j]:
                min_node = j
                min_d = d[j]
        candidates.remove(min_node)
        p[min_node] = cur
        color[cur] = 2
        cur = min_node
        cnt += 1
        #print(cur, d)
        #print(candidates)
        if cnt == n:
            break
    return

dyk(0)
for i in range(n):
    print(i, d[i])