Go: package main

import (
	"bufio"
	"container/heap"
	"fmt"
	"os"
)

type Item struct {
	value    int // The value of the item; arbitrary.
	priority int // The priority of the item in the queue.
	// The index is needed by update and is maintained by the heap.Interface methods.
	index int // The index of the item in the heap.
}
type PriorityQueue []*Item

func (pq PriorityQueue) Len() int { return len(pq) }
func (pq PriorityQueue) Less(i, j int) bool {
	return pq[i].priority < pq[j].priority
}
func (pq PriorityQueue) Swap(i, j int) {
	pq[i], pq[j] = pq[j], pq[i]
	pq[i].index = i
	pq[j].index = j
}
func (pq *PriorityQueue) Push(x interface{}) {
	n := len(*pq)
	item := x.(*Item)
	item.index = n
	*pq = append(*pq, item)
}
func (pq *PriorityQueue) Pop() interface{} {
	old := *pq
	n := len(old)
	item := old[n-1]
	item.index = -1 // for safety
	*pq = old[0 : n-1]
	return item
}

type Q struct {
	pq *PriorityQueue
	ds map[int]int // It has always same value as pq. For random access.
}

func newQ() *Q {
	pq := new(PriorityQueue)
	heap.Init(pq)
	return &Q{
		pq: pq,
		ds: make(map[int]int),
	}
}
func (q *Q) pop() (u, d int) {
	item := heap.Pop(q.pq).(*Item)
	delete(q.ds, item.value)
	return item.value, item.priority
}
func (q *Q) get(u int) (int, bool) { // returns d
	d, ok := q.ds[u]
	return d, ok
}
func (q *Q) set(u, d int) {
	q.ds[u] = d
	for _, item := range *q.pq {
		if item.value != u {
			continue
		}

		item.priority = d
		heap.Fix(q.pq, item.index)
		return
	}
	heap.Push(q.pq, &Item{
		priority: d,
		value:    u,
	})
}
func (q *Q) len() int {
	return len(q.ds)
}

func main() {
	r := bufio.NewReader(os.Stdin)

	var n int
	fmt.Fscan(r, &n)
	cs := make([]map[int]int, n) // []v_i -> c_i
	for h := 0; h < n; h++ {
		var u, k int
		fmt.Fscan(r, &u, &k)
		m := make(map[int]int)
		for i := 0; i < k; i++ {
			var v, c int
			fmt.Fscan(r, &v, &c)
			m[v] = c
		}

		cs[u] = m
	}

	q := newQ()
	q.set(0, 0)
	visited := make(map[int]struct{})
	out := make([]int, n)

	for q.len() > 0 {
		u, d := q.pop()
		for uu, c := range cs[u] {
			// Consider the connection between u and uu.
			if _, ok := visited[uu]; ok {
				continue
			}
			dd := d + c
			if d, ok := q.get(uu); !ok || d > dd {
				q.set(uu, dd)
			}
		}

		out[u] = d
		visited[u] = struct{}{}
	}

	for u, d := range out {
		fmt.Println(u, d)
	}
}

Python: N=int(input())
rinsetu=[[1000000 for i in range(N)] for j in range(N)]
d=[1000000]*(N)
color=["white"]*N
for i in range(N):
    a=list(map(int,input().split()))
    for j in range(a[1]):
        j1=j*2+2
        j2=j*2+3
        rinsetu[i][a[j1]]=a[j2]
def hunterhunter():
    d[0]=0
    while(True):
        mincost=1000000
        for i in range(N):
            if color[i]=="white" and mincost>d[i]:
                mincost=d[i]
                u=i
        if mincost==1000000:break
        color[u]="black"
        for i in range(N):
            if color[i]=="white" and rinsetu[u][i]!=1000000:
                if rinsetu[u][i]+d[u]<d[i]:
                    d[i]=rinsetu[u][i]+d[u]
hunterhunter()
for i,cost in enumerate(d):
    print(i,cost)

Python: n = int(raw_input())
G = [[-1] * n] * n
d = [0] * n
 
for i in range(n):
    v = map(int, raw_input().split())
    for j in range(v[1]):
        G[v[0]][v[2+2*j]] = int(v[3+2*j])
 
flag = [0] * n
tn = [0]
r = 0
while True:
    for i in range(n):
        if flag[i] == 0 and i in tn:
            flag[i] = 1
            d[i] = r
            for j in range(n):
                if G[i][j] != -1 and flag[j] == 0:
                    tn.append(j)
    if len(tn) == n:
        break
    r += 1
 
for i in range(1, n+1):
    print(str(i) + " " + str(d[i]))

Python: from queue import PriorityQueue

def sssp(adj_list):
    n = len(adj_list)
    d = [None]*n
    pq = PriorityQueue()
    pq.put((0, 0)) # d, v

    while(not pq.empty()):
        d_v, v = pq.get()
        if d[v] is not None:
            continue
        d[v] = d_v
        for u, c_vu in adj_list[v]:
            pq.put((d[v]+c_vu, u))

    return d


if __name__ == '__main__':
    n = int(input())
    adj_list = []
    for _ in range(n):
        adj_list.append([])

    for _ in range(n):
        l = list(map(int, input().rstrip().split(' ')))
        u = l[0]
        k = l[1]
        adj_list_for_u = []
        for v, c in zip(l[2::2], l[3::2]):
            adj_list_for_u.append((v,c))
        adj_list[u] = adj_list_for_u

    d = sssp(adj_list)
    for u, d_u in zip(range(n), d):
        print (u, d_u)

Python: from collections import deque

n = int(input())
g = []
d = [10**10] * n
d[0] = 0

for i in range(n):
    temp = list(map(int, input().split()))
    k = temp[1]
    temp = temp[2:]
    adj = []
    for j in range(k):
        v, c = temp[j*2], temp[j*2+1]
        adj.append([v, c])
    g.append(adj)

# for i in range(n):
#     print(g[i])

q = deque()
q.append((0, g[0]))
done = set()

while q:
    node = q.popleft()
    prev = node[0]
    adj = node[1]
    # print('\nadj:', adj)

    for next in adj:
        v = next[0]
        w = next[1]
        # print('v:', v)
        # print('prev:', prev)

        # d[v] = min(d[v], d[prev] + w)
        if d[prev] + w < d[v]:
            d[v] = d[prev] + w
            # Need to add to Q regardless of it's in done or not,
            # because the shortest path was udpated.
            q.append((v, g[v]))
        if v not in done:
            done.add(v)
            q.append((v, g[v]))

# print('d:', d)

for i in range(len(d)):
    print(i, d[i])

Python: n = int(input())
edgeList = []
rootList = [-1 for i in range(n)]
parent = [-1 for i in range(n)]
lenList = [0 for i in range(n)]
sumLength = 0
for i in range(n):
    a = list(map(int, input().split()))
    for j in range(a[1]):
        edgeList.append([a[2*j+3], i, a[2*j+2]])


rootList = [-1 for i in range(n)]
parent = [0 for i in range(n)]
lenList = [float("inf") for i in range(n)]
lenList[0] = 0
def getRoot(x):
    r = rootList[x]
    if r < 0:
        rootList[x] = x
    elif r != x:
        rootList[x] = getRoot(r)
    return rootList[x]

flag = True
while flag:
    flag = False
    edgeList.sort(key=lambda x: (x[0] + lenList[x[1]]))
    for e in edgeList:    # weight:e[0], e[1]->e[2]
        if e[2] == 0:
            continue
        x = getRoot(e[1])
        y = getRoot(e[2])
        if x == 0 != y:
            parent[e[2]] = e[1]
            lenList[e[2]] = lenList[e[1]] + e[0]
            rootList[y] = 0
            flag = True
            break

for i, j in zip(range(n), lenList):
    print(i, j)

Python: n=int(input())
inf=10000000
p=[-1 for i in range(n)]
M=[[inf for j in range(n)] for i in range(n)]
d=[inf for i in range(n)]
color=["white" for i in range(n)]
for i in range(n):
    tmp=list(map(int,input().split()))
    root=tmp[0]
    k=tmp[1]
    for j in range(k):
        v=tmp[2*(j+1)]
        M[root][v]=tmp[2*(j+1)+1]

def dijkstra(s):
    d[s]=0
    while True:
        mincost=inf
        for i in range(n):
            if color[i] is not "black" and d[i]<mincost:
                mincost=d[i]
                u=i
        if mincost is inf:
            break
        color[u]="black"
        for j in range(n):
            if color[j] is not "black" and M[u][j] is not inf:
                if d[u]+M[u][j]<d[j]:
                    d[j]=d[u]+M[u][j]
                    color[j]="gray"
                    p[j]=u

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