Go: package main

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

const BIG_COST = 200000

const (
	ST_NOT_YET = iota
	ST_JOINED
)

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	nNodes := scanInt(sc)

	costs := make([][]int, nNodes)
	graph := make([][]int, nNodes)

	states := make([]int, nNodes)
	costSums := make([]int, nNodes)

	for i := 0; i < nNodes; i++ {
		costs[i] = make([]int, nNodes)
		costSums[i] = BIG_COST
	}

	for i := 0; i < nNodes; i++ {
		u := scanInt(sc)
		k := scanInt(sc)
		graph[u] = make([]int, k)
		for d := 0; d < k; d++ {
			v := scanInt(sc)
			graph[u][d] = v
			costs[u][v] = scanInt(sc)
		}
	}

	costSums[0] = 0
	for {
		minCost := BIG_COST
		var u int

		for i, cost := range costSums {
			if states[i] != ST_JOINED && cost < minCost {
				minCost = cost
				u = i
			}
		}

		if minCost == BIG_COST {
			break
		}

		states[u] = ST_JOINED

		for _, v := range graph[u] {
			cost := minCost + costs[u][v]
			if cost < costSums[v] {
				costSums[v] = cost
			}
		}
	}

	w := bufio.NewWriter(os.Stdout)
	for i, cost := range costSums {
		fmt.Fprintf(w, "%d %d\n", i, cost)
	}
	w.Flush()
}

func scanInt(sc *bufio.Scanner) int {
	sc.Scan()
	v, _ := strconv.Atoi(sc.Text())
	return v
}

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();
    
}