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: 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, readline().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(f"{i} {c}" for i, c in enumerate(d)))
    dijkstra()
MAIN()

Python: from sys import stdin
input = stdin.readline
import heapq

infty = 2**21

def dijkstra(n):
    d = [infty] * n
    color = [0] * n

    d[0] = 0
    PQ = [(0, 0)]
    heapq.heapify(PQ)
    color[0] = 1

    while PQ:
        f = heapq.heappop(PQ)
        u = f[1]
        color[u] = 2

        #最小値を取り出し、それが最短でなければ無視
        if d[u] < f[0]:
            continue

        for adj_u in adj[u]:
            v = adj_u[0]
            if color[v] == 2:
                continue
            if d[v] > d[u] + adj_u[1]:
                d[v] = d[u] + adj_u[1]
                heapq.heappush(PQ, (d[v], v))
                color[v] = 1


    for i in range(n):
        print(str(i) + ' ' + str(-1 if d[i] == infty else d[i]))


n = int(input())

adj = [0]*n

for _ in range(n):
    u, k, *vc = map(int, input().split())
    vx_tuple = [0] * k
    for i, (v, c) in enumerate(zip(vc[::2], vc[1::2])):
        #pythonにはvectorないので、tupleで代用
        vx_tuple[i] = (v, c)
    adj[u] = vx_tuple


dijkstra(n)

C++: #include <map>
#include <set>
#include <list>
#include <cmath>
#include <queue>
#include <stack>
#include <cstdio>
#include <string>
#include <vector>
#include <complex>
#include <cstdlib>
#include <cstring>
#include <numeric>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <functional>
  
#define mp       make_pair
#define pb       push_back
#define all(x)   (x).begin(),(x).end()
#define rep(i,n) for(int i=0;i<(n);i++)
  
using namespace std;
  
typedef    long long          ll;
typedef    unsigned long long ull;
typedef    vector<bool>       vb;
typedef    vector<int>        vi;
typedef    vector<vb>         vvb;
typedef    vector<vi>         vvi;
typedef    pair<int,int>      pii;
  
const int INF=1<<29;
const double EPS=1e-9;
  
const int dx[]={1,0,-1,0,1,1,-1,-1},dy[]={0,-1,0,1,1,-1,-1,1};

typedef pair<int,int> P;

int main() {
    int N;
    cin >> N;
    std::vector<vector<int> > G(N, vector<int>());
    std::vector<vector<int> > dist(N, vector<int>());
    for (int i = 0; i < N; i++) {
        int u, k;
        cin >> u >> k;
        for (int j = 0; j < k; j++) {
            int v, c;
            cin >> v >> c;
            G[u].push_back(v);
            dist[u].push_back(c);
        }
    }

    std::vector<int> d(N, 100000001);
    priority_queue<P, vector<P>, greater<P> > q;
    d[0] = 0;
    q.push(P(0, 0));

    while(!q.empty()) {
        P u = q.top(); q.pop();
        int v = u.second;
        if (d[v] < u.first) {
            continue;
        }
        for (int i = 0; i < G[v].size(); i++) {
            if (d[G[v][i]] > d[v] + dist[v][i]) {
                d[G[v][i]] = d[v] + dist[v][i];
                q.push(P(d[G[v][i]], G[v][i]));
            }
        }
    }

    for (int i = 0; i < N; i++) {
        cout << i << " " << d[i] << endl;
    }
    return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
#include<vector>

using namespace std;

#define WHITE 0
#define BLACK 2
#define GRAY 1
#define MAX 100
#define INFITY 1<<21

int n;
vector<pair<int,int> > adj[MAX];

void dijkstra()
{
	priority_queue<pair<int,int> > PQ;
	int d[MAX],color[MAX],p[MAX];

	for (int i = 0; i < n; ++i)
	{
		d[i]=INFITY;
		p[i]=-1;
		color[i]=WHITE;
	}

	d[0]=0;
	color[0]=GRAY;
	PQ.push(make_pair(0,0));

	while(!PQ.empty()){

		// 把距离最小的顶点加入单源最短路径树
		pair<int,int> f=PQ.top();
		PQ.pop();
		int u=f.second;
		color[u]=BLACK;

		// 更新距离
		for (int i = 0; i < adj[u].size(); ++i)
		{
			int v=adj[u][i].first;
			if (color[v]==BLACK)
			{
				continue;
			}
			if (d[v]>d[u]+adj[u][i].second)
			{
				d[v]=d[u]+adj[u][i].second;
				PQ.push(make_pair(d[v]*-1,v));
				color[v]=GRAY;
				p[v]=u;
			}
		}
	}

	for (int i = 0; i < n; ++i)
	{
		cout<<i<<" "<<(d[i]==INFITY?-1:d[i])<<endl;
	}

}

int main(int argc, char const *argv[])
{
	int u,k,v,c;
	cin>>n;
	for (int i = 0; i < n; ++i)
	{

		cin>>u>>k;
		for (int j = 0; j < k; ++j)
		{
			cin>>v>>c;
			adj[u].push_back(make_pair(v,c));
		}
	}
	dijkstra();
	return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
using namespace std;
static const int INF = 1<<20;
int n;
vector<pair<int, int> > adj[10000];
void dijkstra(){
	priority_queue<pair <int, int> > PQ;
	int color[10000];
	int d[10000];
	for(int i=0; i<n; i++){
		d[i]=INF;
		color[i]=0;
	}
	d[0]=0;
	PQ.push(make_pair(0, 0));
	color[0]=1;
	while(!PQ.empty()){
		pair<int, int> f=PQ.top();
		PQ.pop();
		int u=f.second;
		color[u]=2;
		if(d[u]<f.first*(-1))
			continue;
		for(int j=0; j<adj[u].size(); j++){
			int v=adj[u][j].first;
			if(color[v]==2)
				continue;
			if(d[v]>d[u]+adj[u][j].second){
				d[v]=d[u]+adj[u][j].second;
				PQ.push(make_pair(d[v]*(-1), v));
				color[v]=1;
			}
		}
	}
	for(int i=0; i<n; i++)
		cout<<i<<" "<<(d[i]==INF ? -1 : d[i])<<endl;
}
int main(){
	int k,u,v,c;
	cin>>n;
	for(int i=0; i<n; i++){
		cin>>u>>k;
		for(int j=0; j<k; j++){
			cin>>v>>c;
			adj[u].push_back(make_pair(v, c));
		}
	}
	dijkstra();
	return 0;
}