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: #!/usr/bin/env python
from __future__ import division, print_function
from sys import stdin, maxint


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

    L = []
    for _ in xrange(num):
        L.append([int(s) for s in stdin.readline().split()])

    weight = [maxint] * num
    index = 0
    rearch = {0}
    total_c = 0

    while maxint not in rearch:
        min_v = min_c = maxint
        Li = L[index]
        for i in xrange(Li[1]):
            v = Li[i*2+2]
            if v in rearch:
                continue
            c = Li[i*2+3]
            weight[v] = min(weight[v], c + total_c)
            if min_c > c:
                min_c = c
                min_v = v
        index = min_v
        rearch.add(min_v)
        total_c += min_c

    weight[0] = 0
    for i, d in enumerate(weight):
        print(i, d)


main()

Python: INFINITY = 10 ** 10
WHITE = 0
GRAY = 1
BLACK = 2


n = int(input())
M = [[INFINITY] * n for _ in range(n)]

for _ in range(n):
    u, k, *list_num = map(int, input().split())

    for i in range(0, k * 2, 2):
        M[u][list_num[i]] = list_num[i + 1]

d = [INFINITY] * n

def dijkstra():
    color = [WHITE] * n
    p = [None] * n

    d[0] = 0
    p[0] = -1

    while True:
        cost_min = INFINITY
        for i in range(n):
            if color[i] != BLACK and d[i] < cost_min:
                cost_min = d[i]
                top_now = i

        if cost_min == INFINITY:
            break
    
        color[top_now] = BLACK

        for v in range(n):
            if color[v] == BLACK or M[top_now][v] == INFINITY:
                continue

            cost_now = d[top_now] + M[top_now][v]
            if cost_now < d[v]:
                d[v] = cost_now
                p[v] = top_now
                color[v] = GRAY


dijkstra()

for i, cost in enumerate(d):
    print(i, cost)

Python: n = int(input())
C = [[] for _ in range(n)]
for _ in range(n):
    tmp = list(map(int,input().split()))
    for i in range(1,tmp[1]+1):
        C[tmp[0]].append(tuple(tmp[2*i:2*i+2]))


def dijkstra(start = 0):
    INF = 100000000
    d = [INF]*n
    visited = [False]*n

    d[start] = 0
    visited[start] = True
    S = {start}

    while 1:
        for s in S:
            for adj_weight in C[s]:
                if visited[adj_weight[0]] == False:
                    d[adj_weight[0]] = min(d[s] + adj_weight[1],d[adj_weight[0]])
        
        min_d = INF
        min_node = -1
        for i in range(n):
            if visited[i] == False and d[i] < min_d:
                min_d = d[i]
                min_node = i
        if min_node == -1:
            break
        else:
            visited[min_node] = True
            S.add(min_node)
    return d

ans = dijkstra()
for i in range(n):
    print("{} {}".format(i,ans[i]))

Python: def relax(u, v, w):
    if D[u] + w < D[v]:
        D[v] = D[u] + w
        P[v] = u

INF = float('inf')
N = int(input())
D = [INF for i in range(N)]
P = [None for i in range(N)]
C = ['w' for i in range(N)]
D[0] = 0

G = [[INF for j in range(N)] for i in range(N)]
for i in range(N):
    x = list(map(int, input().split()))
    g = x[2:]
    for j, n in enumerate(g):
        if j % 2 == 0:
            G[i][n] = g[j + 1]


while True:
    mincost = INF
    u = -1
    for i in range(N):
        if C[i] != 'b' and D[i] < mincost:
            mincost = D[i]
            u = i
    if u == -1:
        break
    C[u] = 'b'
    for v, w in enumerate(G[u]):
        if w != INF and C[v] != 'b':
            relax(u, v, w)
            C[v] = 'g'

for i, d in enumerate(D):
    print('{0} {1}'.format(i, d))

Python: from heapq import heappush, heappop
from collections import deque

def main():
    INF = float('inf')
    V = int(input())
    dist = [INF] * V
    visited = [False] * V
    graph = [None] + [deque() for i in range(V-1)]
    
    q = []
    tmp = list(map(int, input().split()))
    for i in range(tmp[1]): heappush(q, (tmp[2+2*i+1], tmp[2+2*i]))
        
    for i in range(1, V):
        tmp = list(map(int, input().split()))
        
        for j in range(tmp[1]):
            graph[i].append((tmp[2+2*j+1], tmp[2+2*j]))
        
    dist[0], visited[0] = 0, True
        
    while q:
        cost, v = heappop(q)
        if visited[v]: continue
    
        visited[v] = True
        dist[v] = cost
        
        for c, u in graph[v]:
            if visited[u] or dist[u] < cost + c: continue
            heappush(q, (cost+c, u))
    
    for i in range(V): print(i, dist[i])
        
if __name__ == '__main__':
    main()

Python: n = int(input())
g = [[2**64]*n for i in range(n)]
for i in range(n):
    u, k, *l, = map(int, input().split())
    for j in range(k):
        v, c = l[j*2], l[j*2+1]
        g[u][v] = c

'''
ダイクストラ法による単一始点最短経路
'''
d = [2**64]*n
d[0] = 0

s = []
v = [i for i in range(n)]
while len(s) < n:
    c, u = 2**32, -1
    for vv in v:
        if d[vv] < c:
            c, u = d[vv], vv
    s.append(u)
    v.remove(u)
    for i, c in enumerate(g[u]):
        if i in v and d[u]+g[u][i] < d[i]:
            d[i] = d[u]+g[u][i]

for i in range(n):
    print(f"{i} {d[i]}")