Go: package main

import (
	"bufio"
	"fmt"
	"os"
)

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

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

		out[u] = q[u]
		delete(q, u)
		visited[u] = struct{}{}
	}

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

func top(q map[int]int) int {
	minu := -1
	min := -1
	for u, d := range q {
		if min < 0 || d < min {
			minu = u
			min = d
		}
	}

	return minu
}

C++: #include <iostream>
#include <string>
#include <cstring>
#include <fstream>
#include <cmath>
#include <iomanip>
#include <cstdlib>
#include <algorithm>
#include <vector>
#include <map>
#include <deque>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <list>
#include <unordered_map>

using namespace std;

static const int MAX = 100;
static const int INFTY = (1<<21);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n, M[MAX][MAX];

void dijkstra(){
    int minv;
    int d[MAX], color[MAX];

    for (int i=0;i<n;i++){
        d[i] = INFTY;
        color[i] = WHITE;
    }

    d[0] = 0;
    color[0] = GRAY;
    while (true){
        minv = INFTY;
        int u= -1;
        for (int i=0;i<n;i++){
            if(minv > d[i] and color[i] != BLACK){
                u = i;
                minv = d[i];
            }
        }
        if (u==-1){
            break;
        }
        color[u] = BLACK;
        for (int v=0;v<n;v++){
            if (color[v] != BLACK and M[u][v] != INFTY){
                if (d[v] > d[u] + M[u][v]){
                    d[v] = d[u] + M[u][v];
                    color[v] = GRAY;
                }
            }
        }
    }
    for (int i=0;i<n;i++){
        cout << i << " " << (d[i] == INFTY ? -1 : d[i]) << endl;
    }

}

int main(){
    
    cin >> n;
    for (int i=0;i<n;i++){
        for (int j=0;j<n;j++){
            M[i][j] = INFTY;
        }
    }
    int k,c,u,v;
    for (int i=0;i<n;i++){
        cin >> u >> k;
        for (int j=0;j<k;j++){
            cin >> v >> c;
            M[u][v] = c;
        }
    }

    dijkstra();
}

C++: #include<iostream>
using namespace std;
const int MAX = 100, INF = 1e9, WHITE = 0, GRAY = 1, BLACK = 2;

int n, M[MAX][MAX];

void dijkstra(){
    int minv;
    int d[MAX], color[MAX];
    for (int i = 0; i < n; i++)
    {
        d[i] = INF;
        color[i] = WHITE;
    }
    
    d[0] = 0;
    color[0] = GRAY;
    while (true)
    {
        minv = INF;
        int u = -1;
        for (int i = 0; i < n; i++){
            if (minv > d[i] && color[i] != BLACK){
                u = i;
                minv = d[i];
            }
        }
        if (u == -1) break;
        color[u] = BLACK;
        for (int v = 0; v < n; v++)
        {
            if (color[v] != BLACK && M[u][v] != INF)
            {
                if (d[v] > d[u] + M[u][v])
                {
                    d[v] = d[u] + M[u][v];
                    color[v] = GRAY;
                }   
            }
        }
        
    }
    for (int i = 0; i < n; i++)
    {
        cout << i << " " << (d[i] == INF ? -1 : d[i]) << endl;
    }
    
}

int main(){
    cin >> n;
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < n; j++)
        {
            M[i][j] = INF;
        }
        
    }
    int k, c, u, v;
    for (int i = 0; i < n; i++)
    {
        cin >> u >> k;
        for (int j = 0; j < k; j++)
        {
            cin >> v >> c;
            M[u][v] = c;
        }
        
    }
    dijkstra();
    
}