Go: package main

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

// I/O
type Scanner struct {
	sc *bufio.Scanner
}

func NewScanner() *Scanner {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Buffer(make([]byte, 1024), int(1e+9))
	return &Scanner{sc}
}

func (s *Scanner) nextStr() string {
	s.sc.Scan()
	return s.sc.Text()
}

func (s *Scanner) nextInt() int {
	i, e := strconv.Atoi(s.nextStr())
	if e != nil {
		panic(e)
	}
	return i
}

func (s *Scanner) nextFloat() float64 {
	f, e := strconv.ParseFloat(s.nextStr(), 64)
	if e != nil {
		panic(e)
	}
	return f
}

func (s *Scanner) nextRuneSlice() []rune {
	return []rune(s.nextStr())
}

func (s *Scanner) nextIntSlice(n int) []int {
	res := make([]int, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextInt()
	}
	return res
}

func (s *Scanner) nextFloatSlice(n int) []float64 {
	res := make([]float64, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextFloat()
	}
	return res
}

// Arithmetic
func max(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m < i {
			m = i
		}
	}
	return m
}

func min(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m > i {
			m = i
		}
	}
	return m
}

func abs(x int) int {
	if x > 0 {
		return x
	}
	return -x
}

func pow(x, y int) int {
	res := 1
	for i := 0; i < y; i++ {
		res *= x
	}
	return res
}

func ceil(a, b int) int {
	if a%b == 0 {
		return a / b
	} else {
		return a/b + 1
	}
}

// Sort
type RuneSlice []rune

func (a RuneSlice) Len() int           { return len(a) }
func (a RuneSlice) Less(i, j int) bool { return a[i] < a[j] }
func (a RuneSlice) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }

// Main
const INF = 1 << 60

type Edge struct {
	to, cost int
}

type Node struct {
	id, cost int
}

type PQ []Node

func (pq PQ) Len() int           { return len(pq) }
func (pq PQ) Less(i, j int) bool { return pq[i].cost < pq[j].cost }
func (pq PQ) Swap(i, j int)      { pq[i], pq[j] = pq[j], pq[i] }

func (pq *PQ) Push(x interface{}) {
	*pq = append(*pq, x.(Node))
}

func (pq *PQ) Pop() interface{} {
	old := *pq
	n := len(old)
	x := old[n-1]
	*pq = old[0 : n-1]
	return x
}

func main() {
	sc := NewScanner()
	wtr := bufio.NewWriter(os.Stdout)
	N := sc.nextInt()
	E := make([][]Edge, N)
	for i := 0; i < N; i++ {
		id, k := sc.nextInt(), sc.nextInt()
		E[id] = make([]Edge, k)
		for j := 0; j < k; j++ {
			to, cost := sc.nextInt(), sc.nextInt()
			E[id][j] = Edge{to, cost}
		}
	}

	d := make([]int, N)
	for i := 0; i < N; i++ {
		d[i] = INF
	}
	done := make([]bool, N)
	pq := &PQ{}
	heap.Init(pq)
	d[0] = 0
	heap.Push(pq, Node{0, 0})
	for pq.Len() > 0 {
		cur := heap.Pop(pq).(Node).id
		if done[cur] {
			continue
		}
		done[cur] = true
		for i := 0; i < len(E[cur]); i++ {
			to, cost := E[cur][i].to, E[cur][i].cost+d[cur]
			if !done[to] && cost < d[to] {
				d[to] = cost
				heap.Push(pq, Node{to, cost})
			}
		}
	}

	for i := 0; i < N; i++ {
		fmt.Fprintln(wtr, i, d[i])
	}
	wtr.Flush()
}

C++: #include <cmath>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <climits>
#include <map>
#include <list>
#include <stack>
#include <queue>
#include <vector>
#include <string>
#include <sstream>
#include <fstream>
#include <iostream>
#include <algorithm>
using namespace std;

int *c;

struct job {
	int id;
	job(int i){
		this->id = i;
	}
	bool operator<(job j) const {
		return c[this->id] > c[j.id];
	}
};

int main() {
	int n;
	scanf("%d", &n);
	
	c = new int[n];
	vector<vector<pair<int, int> > > paths;
	
	for(int i = 0; i < n; i++){
		int u, k;
		scanf("%d %d", &u, &k);
		
		vector<pair<int, int> > path;
		c[u] = u ? INT_MAX : 0;
		while(k--){
			int v, c;
			scanf("%d %d", &v, &c);
			path.push_back(make_pair(v, c));
		}
		paths.push_back(path);
	}
	
	priority_queue<job> q;
	q.push(job(0));
	while(q.size()){
		int i = q.top().id;
		q.pop();
		
		for(int j = 0; j < paths[i].size(); j++){
			int dest = paths[i][j].first;
			int cost = paths[i][j].second;
			if(c[dest] > c[i] + cost){
				c[dest] = c[i] + cost;
				q.push(job(dest));
			}
		}
	}
	
	for(int i = 0; i < n; i++){
		printf("%d %d\n", i, c[i]);
	}
}

C++: #include <iostream>
#include <vector>
#include <queue>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> Pair;
ll inf = 1e10;
int MAX_V;

ll V, E;
vector<Pair> G[100010];
ll d[100010];

void dijkstra(ll s) {
    priority_queue<Pair, vector<Pair>, greater<Pair>> que;
    fill(d, d + V, inf);
    d[s] = 0;
    que.push(Pair(0, s));
    
    while (!que.empty()) {
        Pair p = que.top();
        que.pop();
        
        ll v = p.second;
        if (d[v] < p.first) continue;
        for (int i = 0; i < G[v].size(); i++) {
            Pair e = G[v][i];
            if (d[e.first] > d[v] + e.second) {
                d[e.first] = d[v] + e.second;
                que.push(Pair(d[e.first], e.first));
            }
        }
    }
}

int main() {
    cin >> V;
    for (int i = 0; i < V; i++) {
        int a, et;
        cin >> a >> et;
        for (int j = 0; j < et; j++) {
            int b;
            ll r;
            cin >> b >> r;
            G[a].emplace_back(b, r);
            //G[b].emplace_back(a, r);
        }
    }

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

}

C++: #include <bits/stdc++.h>
using namespace std;

static const int N = 10001;
static const int INF = (1 << 30);
static const int WHITE = 0;
static const int GRAY  = 1;
static const int BLACK = 2;

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

void dijkstra(){
    priority_queue<pair<int,int> > p_q;
    int color[N];
    int d[N];
    for(int i=0;i<n;i++){
        d[i] = INF;
        color[i] = GRAY;
    }

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

    while(!p_q.empty()){
        pair<int,int> f = p_q.top();
        p_q.pop();
        int u = f.second;
        color[u] = BLACK;

        if(d[u] < f.first*-1) continue;

        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;
                p_q.push(make_pair(d[v]*-1,v));
                color[v] = GRAY;
            }
        }
    }

    for(int i=0;i<n;i++){
        cout << i << ' ';
        if(d[i] == INF)
            cout << -1;
        else 
            cout << d[i];
        cout << 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();
}

C++: #include <iostream>
#include <limits.h>
#include <vector>
#include <queue>

using namespace std;

struct Node {
    int id;
    int cost;
    bool done;
    vector<int> next_node;
    vector<int> len_cost;

    bool operator<(const Node& right) const {
        return cost > right.cost;
    }
} node[10000];

int main() {
    int n, id, k;

    cin >> n;
    for (int i = 0; i < n; i++) {
        cin >> id >> k;
        node[id].id = id;
        node[id].cost = INT_MAX;
        node[id].done = false;
        node[id].next_node.resize(k);
        node[id].len_cost.resize(k);
        for (int j = 0; j < k; j++) {
            cin >> node[id].next_node[j] >> node[id].len_cost[j];
        }
    }

    priority_queue<Node> q;
    node[0].cost = 0;
    q.push(node[0]);
    while (!q.empty()) {
        Node temp = q.top();
        q.pop();

        if (temp.done == true) {
            continue;
        }
        node[temp.id].done = true;

        for (int i = 0; i < temp.next_node.size(); i++) {
            int to = temp.next_node[i];
            int cost = temp.cost + temp.len_cost[i];
            if (node[to].cost > cost) {
                node[to].cost = cost;
                q.push(node[to]);
            }
        }
    }

    for (int i = 0; i < n; i++) {
        cout << i << " " << node[i].cost << endl;
    }
    
    return 0;
}