Go: package main

import (
	"bufio"
	"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
type Node struct {
	cost int
	done bool
}

type Edge struct {
	to, cost int
}

const INF = 1 << 60

func main() {
	sc := NewScanner()
	wtr := bufio.NewWriter(os.Stdout)
	N := sc.nextInt()
	nodes := make([]Node, N)
	for i := 0; i < N; i++ {
		nodes[i].cost = INF
	}
	E := make([][]Edge, N)
	for i := 0; i < N; i++ {
		id, k := sc.nextInt(), sc.nextInt()
		for j := 0; j < k; j++ {
			to, cost := sc.nextInt(), sc.nextInt()
			E[id] = append(E[id], Edge{to, cost})
		}
	}
	nodes[0].cost = 0
	for {
		cur := 0
		minCost := INF
		for i := 0; i < N; i++ {
			n := nodes[i]
			if !n.done && n.cost < minCost {
				cur = i
				minCost = n.cost
			}
		}
		if minCost == INF {
			break
		}
		nodes[cur].done = true
		for i := 0; i < len(E[cur]); i++ {
			to, cost := E[cur][i].to, E[cur][i].cost+nodes[cur].cost
			if !nodes[to].done && cost < nodes[to].cost {
				nodes[to].cost = cost
			}
		}
	}

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

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

#define NIL -1
#define MAX (1 << 24)

struct Node {
	int dis = MAX;
	bool flag = false;
	vector<int> d;
	vector<int> id;
};

void dijkstra(vector<Node>& u)
{
	u[0].dis = 0;

	while (1)
	{
		int mini = MAX;
		int n;
		for (int i = 0; i < u.size(); i++)
		{
			if (!u[i].flag && u[i].dis < mini) {
				mini = u[i].dis;
				n = i;
			}
		}

		if (mini == MAX) return;
		u[n].flag = true;

		for (int i = 0; i < u[n].id.size(); i++)
		{
			if (u[u[n].id[i]].flag) continue;
			if ((u[n].dis + u[n].d[i]) < u[u[n].id[i]].dis) {
				u[u[n].id[i]].dis = u[n].dis + u[n].d[i];
			}
		}
	}
}

int main(void)
{
	int i, N, v, k, c, x;
	cin >> N;
	vector<Node> u(N);
	for (i = 0; i < N; i++)
	{
		cin >> v >> k;
		for (int j = 0; j < k; j++)
		{
			cin >> x >> c;
			u[v].id.push_back(x);
			u[v].d.push_back(c);
		}
	}

	
	dijkstra(u);

	for (i = 0; i < N; i++) cout << i << " " << u[i].dis << endl;

	return 0;
}

C++: #include <cstdio>
#include <iostream>
#include <queue>
#include <utility>
#include <vector>

using namespace std;

int main() {

	int INF = 100001;

	int n;
	scanf("%d", &n);

	vector<pair<int, int>> G[n];
	for (int i = 0; i < n; ++i) {
		int from;
		scanf("%d", &from);

		int v;
		scanf("%d", &v);

		for (int j = 0; j < v; ++j) {
			int to;
			int w;
			scanf("%d %d", &to, &w);
			G[from].push_back(make_pair(to, w));
		}
	}

	int C[n];
	for (int i = 0; i < n; ++i)
		C[i] = INF;

	int color[n];
	int WHITE = 0;
	int BLACK = 1;
	for (int i = 0; i < n; ++i)
		color[i] = WHITE;

	priority_queue<pair<int, int>> PQ;
	PQ.push(make_pair(0, 0));
	C[0] = 0;
	while (!PQ.empty()) {
		int u = PQ.top().second;
		PQ.pop();
		color[u] = BLACK;
		for (int i = 0; i < (int) G[u].size(); ++i) {
			auto c = G[u][i];
			if (color[c.first] != BLACK && c.second + C[u] < C[c.first]) {
				C[c.first] = c.second + C[u];
				PQ.push(make_pair(C[c.first] * -1, c.first));
			}
		}
	}

	for (int i = 0; i < n; ++i) {
		cout << i << " " << C[i] << endl;
	}

	return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <map>
#include <numeric>
#include <string>
#include <cmath>
#include <iomanip>
#include <queue>
#include <list>
#include <stack>
#include <cctype>
#include <cmath>

using namespace std;

/* typedef */

typedef long long ll;

/* constant */

const int INF = 1 << 30;
const int MAX = 100;
const int mod = 1000000007;
const double pi = 3.141592653589;

const int WHITE = 0;
const int GRAY = 1;
const int BLACK = 2;

/* global variables */
vector< vector<pair<int, int> > > Adj(MAX, vector<pair<int, int> >());
vector<int> color(MAX, WHITE);
vector<int> d(MAX, INF);
vector<int> p(MAX, -1);
int n;

/* function */
void dijkstra();

/* main */
int main() {
    
    cin >> n;
    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;
            Adj[u].push_back(make_pair(v, c));
        }
    }

    dijkstra();

    for (int i = 0; i < n; i++ ) {
        cout << i << ' ' << d[i] << '\n';
    }
   

}

void dijkstra() {

    pair<int, int> p1;
    d[0] = 0;
    p[0] = -1;

    priority_queue<pair<int, int> > PQ;
    PQ.push(make_pair(0, 0));

    while (!PQ.empty()) {

        p1 = PQ.top(); PQ.pop();
        int u = p1.second;
        color[u] = BLACK;

        if ( d[u] < p1.first * (-1) ) continue;

        for (auto p2 : Adj[u]) {

            int v = p2.first;
            int cost = p2.second;

            if (color[v] != BLACK) {
                if (d[u] + cost < d[v]) {
                    p[v] = u;
                    d[v] = d[u] + cost;
                    color[v] = GRAY;
                    PQ.push(make_pair(-d[v], v));
                }
            }
        }
    }

}

C++: #include<bits/stdc++.h>

using namespace std;
int d[10002];
struct Edge{
    int from,to,w;
};
const int inf=1<<30;
vector<Edge> E;
vector<int> G[10002];
struct node{
    int to,w;
    friend bool operator < (const node& a, const node& b){
        return a.w>b.w;
    }
};
bool vis[10002];
int V;
void dijkstar(int start=0){
    priority_queue<node> que;
    que.push(node {start,0});
    d[start]=0;
    while(!que.empty()){
        node s=que.top();
        que.pop();
        int nowV=s.to,w=s.w;
        if(vis[nowV]) continue;
        vis[nowV]=true;
        for(int i=0;i<G[nowV].size();i++){
            Edge ee=E[G[nowV][i]];
            if(d[ee.to]>d[nowV]+ee.w){
                d[ee.to]=d[nowV]+ee.w;
                que.push(node {ee.to,d[ee.to]});
            }
        }
    }
}

int main(){
    cin>>V;
    for(int i=0;i<V;i++){
        int id,k;
        cin>>id>>k;
        vis[i]=false;
        d[i]=inf;
        while(k--){
            int out,val;
            cin>>out>>val;
            E.push_back(Edge{id,out,val});
            G[id].push_back(E.size()-1);
        }
    }
    dijkstar();
    for(int i=0;i<V;i++){
        cout<<i<<" "<<d[i]<<endl;
    }
}