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: #!/usr/bin/env python
# -*- coding: utf-8 -*-

"""
input:
5
0 3 2 3 3 1 1 2
1 2 0 2 3 4
2 3 0 3 3 1 4 1
3 4 2 1 0 1 1 4 4 3
4 2 2 1 3 3

output:
0 0
1 2
2 2
3 1
4 3
"""

import sys
import heapq as hp

WHITE, GRAY, BLACK = 0, 1, 2


def generate_adj_table(v_table):
    for each in v_table:
        v_index, v_adj_length, *v_adj_list = map(int, each)
        # assert len(v_adj_list) == v_adj_length * 2
        for pair in zip(v_adj_list[::2], v_adj_list[1::2]):
            init_adj_table[v_index][pair[0]] = pair[1]

    return init_adj_table


def dijkstra_path_heap():
    # path search init
    distance[init_vertex] = 0
    path_heap = []
    # heapq: rank by tuple[0], at here it's d[u]
    hp.heappush(path_heap, (0, init_vertex))

    while path_heap:
        current = hp.heappop(path_heap)[1]

        color[current] = BLACK

        for adj, cost in adj_table[current].items():
            if color[adj] is not BLACK:
                # alt: d[u] + w[u,v]
                alt_path = distance[current] + cost
                if alt_path < distance[adj]:
                    # update path_list
                    distance[adj] = alt_path
                    # update heap
                    hp.heappush(path_heap, (alt_path, adj))
                    color[adj] = GRAY
                    parents[adj] = current

    return distance


if __name__ == '__main__':
    _input = sys.stdin.readlines()
    vertices = int(_input[0])
    v_info = map(lambda x: x.split(), _input[1:])
    # assert len(init_vertices_table) == vertices_num

    distance = [float('inf')] * vertices
    parents = [-1] * vertices
    color = [WHITE] * vertices
    init_adj_table = tuple(dict() for _ in range(vertices))
    init_vertex = 0

    adj_table = generate_adj_table(v_info)
    ans = dijkstra_path_heap()
    for i, v in enumerate(ans):
        print(i, v)

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

if __name__ == '__main__':

    n = int(input())
    M = [set() for i in range(n)]

    for i in range(n):
        l = list(map(int, input().split(" ")))
        for k in range(l[1]):
            j = l[2 + 2 * k]
            c = l[2 + 2 * k + 1]
            M[i].add((j, c))

    d = [float("inf")] * n
    h = []

    def dijkstra(s):
        color = [0] * n
        p = [None] * n
        d[s] = 0
        heappush(h, (d[s], s))

        while h:
            _, u = heappop(h)

            color[u] = 2

            for v, c in M[u]:
                if color[v] != 2:
                    if d[u] + c < d[v]:
                        d[v] = d[u] + c
                        color[v] = 1
                        heappush(h, (d[v], v))

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

Python: import sys
readline = sys.stdin.readline
from heapq import heapify, heappush, heappop
INF = float("inf")
def MAIN():
    n = int(input())
    adj = [[]] * n
    for _ in range(0, n):
        U = list(map(int, input().split()))
        adj[U[0]] = zip(U[2::2], U[3::2])
    def dijkstra():
        d = [0] + [INF] * (n - 1)
        hq = [(0, 0)]
        while hq:
            u = heappop(hq)[1]
            for v, c in adj[u]:
                alt = d[u] + c
                if d[v] > alt:
                    d[v] = alt
                    heappush(hq, (alt, v))
        print("\n".join(" ".join(map(str, (i, c))) for i, c in enumerate(d)))
    dijkstra()
MAIN()

Python: import heapq as pq
inf = float("inf")
n = int(input())
M = [[inf for i in range(n)] for i in range(n)]
for i in range(n):
    L = list(map(int, input().split()))
    for j in range(L[1]):
        M[L[0]][L[2 * j + 2]] = L[2 * j + 3]


def dijkstra(s):
    color = [0] * n
    d = [inf] * n
    d[s] = 0
    H =[]
    pq.heappush(H, [0, s])

    while len(H) != 0:
        u2,u1 = pq.heappop(H)
        color[u1] = 1
        if d[u1] < u2:
            continue
        for v in range(n):
            if color[v] != 1 and M[u1][v] != inf:
                if d[u1] + M[u1][v] < d[v]:
                    d[v] = d[u1] + M[u1][v]
                    pq.heappush(H, [d[v], v])
    return d

d = dijkstra(0)
for i,v in enumerate(d):
 print("{} {}".format(i,v))

Python: #ALDS_1_12_C Single Source Shortest Path II
import sys
import heapq

n = int(input())
G = [[] for _ in range(n)]
for i in range(n):
    u, k, *vc = list(map(int, sys.stdin.readline().strip().split()))
    for j in range(k):
        G[u].append([vc[j * 2], vc[j * 2 + 1]])

p = [] * n
c = ['white'] * n
d = [] * n
heapq.heappush(d, (0, 0))  # (distance, node)

mindist = [float('inf')] * n
mindist[0] = 0

while d:
    now = heapq.heappop(d)[1]

    #  色識別はなくても実行可能だが、枝刈りのために実行
    if c[now] == 'black':
        continue
    c[now] = 'black'

    for i in G[now]:
        if mindist[now] + i[1] < mindist[i[0]]:
            mindist[i[0]] = mindist[now] + i[1]
            heapq.heappush(d, [mindist[i[0]], i[0]])

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