Go: package main

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

const (
	MAX_N      = 10000
	MAX_WEIGHT = 100000
)

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

	sssp([]int{1}, shortestList, adjacentMatrix)
	for _, v := range shortestList {
		fmt.Printf("%d %d\n", v.getEnd()-1, v.shortest)
	}
}

func (si ShortestInfo) getEnd() int {
	if len(si.edges) == 0 {
		return 1
	} else {
		return si.edges[len(si.edges)-1].end
	}
}

func createAdjacentMatrix(n int, sc *bufio.Scanner) ([][]int, error) {
	adjacentMatrix := make([][]int, n)
	for i := 0; i < n; i++ {
		id, err := nextInt(sc)
		if err != nil {
			return nil, err
		}
		adjacentMatrix[id] = make([]int, n)
		for j := 0; j < n; j++ {
			adjacentMatrix[id][j] = -1
		}
		vertexNum, err := nextInt(sc)
		if err != nil {
			return nil, err
		}
		for j := 0; j < vertexNum; j++ {
			v, err := nextInt(sc)
			if err != nil {
				return nil, err
			}
			c, err := nextInt(sc)
			if err != nil {
				return nil, err
			}
			adjacentMatrix[id][v] = c
		}
	}
	return adjacentMatrix, nil
}

func sssp(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]
			if currentShortest.shortest+adj.weight < getShortest(adj.end, shortestList).shortest {
				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: V=int(input())

G=[[] for i in range(V)]
d=[1001001001 for i in range(V)]

import heapq

def dijkstra(s):
    q=[]
    d[s]=0
    heapq.heappush(q,(0, s))
    
    while(len(q)):
        
        p=heapq.heappop(q)
        v=p[1]
        if d[v]<p[0]:
            continue
        for e in G[v]:
            if d[e[0]]>d[v]+e[1]:
                d[e[0]]=d[v]+e[1]
                
                heapq.heappush(q, (d[e[0]], e[0]))

import sys
for l in sys.stdin:
    l=list(map(int,l.split()))
    u=l[0]
    k=l[1]
    G[u]=zip(*[iter(l[2:])]*2)
    
dijkstra(0)
for i,c in enumerate(d):
    print(i, c)

Python: #!/usr/bin/env python
from __future__ import division, print_function
from sys import stdin, maxint
from heapq import heappush, heappop, heapify


def main():
    num = int(stdin.readline())

    edges = []
    for _ in xrange(num):
        it = iter(int(s) for s in stdin.readline().split()[1:])
        edges.append([(next(it), next(it)) for _ in xrange(next(it))])

    distances = [[maxint, v] for v in xrange(num)]
    distances[0][0] = 0
    V = set(xrange(1, num))

    if num == 1000:
        solve1000(edges, distances, V)
    else:
        solve(edges, distances, V)

    for d, i in distances:
        print(i, d)


def solve1000(edges, distances, V):
    candidate = []
    mark = set()
    index = 0

    while V:
        for end, cost in edges[index]:
            if end not in V:
                continue
            cost += distances[index][0]
            if distances[end][0] > cost:
                distances[end][0] = cost
                if end not in mark:
                    heappush(candidate, distances[end])
                    mark.add(end)
                else:
                    heapify(candidate)

        index = heappop(candidate)[1]
        mark.remove(index)
        V.discard(index)


def solve(edges, distances, V):
    candidate = []
    index = 0

    while V:
        for end, cost in edges[index]:
            if end not in V:
                continue
            cost += distances[index][0]
            if distances[end][0] > cost:
                distances[end][0] = cost
                heappush(candidate, distances[end])

        index = heappop(candidate)[1]
        V.discard(index)


main()

Python: import heapq


def dijkstra(adj_list, n):
    dist = [float("inf") for i in range(n)]
    visited = [False for _ in range(n)]
    parent = [-1 for _ in range(n)]
    start = 0
    dist[start] = 0
    dist_heap = []  # 距離が最小のノードをすぐに探せるようにするために使う。次のノードの候補を入れる。
    heapq.heappush(dist_heap, (dist[start], start))

    while len(dist_heap) > 0:
        cost, start = heapq.heappop(dist_heap)  # 一番近いノードがスタート地点となる
        visited[start] = True
        if dist[start] < cost:  # heapのコストが最短でなければ、distを更新する必要はない
            continue
        for end, weight in adj_list[start]:
            # startから出ているノードの距離を計算してheapqに入れる
            if not visited[end] and dist[start] + weight < dist[end]:
                dist[end] = dist[start] + weight
                parent[end] = start
                heapq.heappush(dist_heap, (dist[end], end))

    return parent, dist


def main():
    n = int(input())
    adj_list = []
    for _ in range(n):
        row = []
        line = input().split()
        dim = int(line[1])
        for i in range(dim):
            row.append((int(line[2 + i * 2]), int(line[2 + i * 2 + 1])))  # 番号, 重み
        adj_list.append(row)
    _, dist = dijkstra(adj_list, n)
    for i in range(n):
        print("{} {}".format(i, dist[i]))


if __name__ == "__main__":
    main()

Python: # -*- coding: utf-8 -*-
from heapq import heappop, heappush

N = int(input())
INF = 1 << 12
adj = [[] for _ in range(N)]

for n in range(N):
    inp = tuple(map(int, input().split()))
    adj[n] = list(zip(inp[2::2], inp[3::2]))

def dijkstra():
    d = [INF for n in range(N)]
    d[0] = 0
    heap = [[0, 0]]
    while len(heap):
        pcost, p = heappop(heap)
    
        for v, c in adj[p]:
            new_cost = d[p] + c
            if new_cost < d[v]:
                d[v] = new_cost
                heappush(heap, [new_cost, v])
    for n in range(N):
        print("{} {}".format(n, d[n]))

dijkstra()

Python: n = int(input())
G = [[-1 for i in range(n)] for j in range(n)]
d = [999999 for i in range(n)]
  
for i in range(n):
    v = input().split()
    for j in range(int(v[1])):
        G[int(v[0])][int(v[2+2*j])] = int(v[3+2*j])

d = [999999] * n
flag = [0] * n
d[0] = 0
while True:
    v = -1
    for j in range(n):
        if flag[j] != 1 and (v == -1 or d[j] < d[v]):
            v = j
    if v == -1:
        break
    flag[v] = 1
    for j in range(n):
        if G[v][j] == -1: continue
        d[j] = min(d[j], d[v] + G[v][j])

for i in range(n):
    print(str(i) + " " + str(d[i]))