Go: package main

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

func getScanner(fp *os.File) *bufio.Scanner {
	scanner := bufio.NewScanner(fp)
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 500001), 500000)
	return scanner
}

func getNextString(scanner *bufio.Scanner) string {
	scanner.Scan()
	return scanner.Text()
}

func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}

func main() {
	fp := os.Stdin
	if len(os.Args) > 1 {
		fp, _ = os.Open(os.Args[1])
	}

	scanner := getScanner(fp)
	writer := bufio.NewWriter(os.Stdout)

	n := getNextInt(scanner)

	g := makeGraph(n)
	for i := 0; i < n; i++ {
		u := getNextInt(scanner)
		k := getNextInt(scanner)
		for ii := 0; ii < k; ii++ {
			v := getNextInt(scanner)
			c := getNextInt(scanner)
			g[u][v] = c
		}
	}

	ans := make([]int, n)
	im := make(IntMap, 1)
	im.increment(0)
	for len(im) < n {
		min := 1 << 30
		x := -1
		for u := range im {
			for v := 0; v < n; v++ {
				if im.get(v) != 0 {
					continue
				}
				if min > ans[u]+g[u][v] {
					min = ans[u] + g[u][v]
					x = v
				}
			}
		}
		im.increment(x)
		ans[x] = min
	}

	for i := 0; i < n; i++ {
		fmt.Fprintln(writer, fmt.Sprintf("%d %d", i, ans[i]))
	}
	writer.Flush()
}

func makeGraph(n int) [][]int {
	g := make([][]int, n)
	for i := 0; i < n; i++ {
		g[i] = make([]int, n)
		for ii := 0; ii < n; ii++ {
			g[i][ii] = 1 << 30
		}
	}

	return g
}

// IntMap ...
type IntMap map[int]int

func (m IntMap) get(key int) int {
	if _, ok := m[key]; ok {
		return m[key]
	}
	return 0
}
func (m IntMap) increment(key int) {
	if _, ok := m[key]; ok == false {
		m[key] = 0
	}
	m[key]++
}

C++: #include <iostream>
#include <cstdio>
#include <cstdlib>
#include <stack>
#include <vector>
#include <algorithm>
#include <cmath>
#include <climits>
#include <cstring>
#include <queue>
#include <string>


using namespace std;

const double PI = 3.14159265358979;

int G[101][101];
int visited[101];
int n;

int d[101];
int p[101];

void dijkstra(int startpoint) {

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

	d[startpoint] = 0;

	while (true) {

		int minx = INT_MAX;
		int u = -1;
		for (int i = 0; i < n; i++)	{
			if (!visited[i] && minx > d[i]) {
				minx = d[i];
				u = i;
			}
		}
		if (u == -1) break;

		visited[u] = 1;
		
		for (int i = 0; i < n; i++)	{
			if (!visited[i] && G[u][i] < INT_MAX) {
				if (d[u] + G[u][i] < d[i]) {
					d[i] = d[u] + G[u][i];
					p[i] = u;
				}
			}
		}
	}
}

int main() {
	
	
	cin >> n;
	for (int i = 0; i < n; i++)	{
		for (int j = 0; j < n; j++) {
			G[i][j] = INT_MAX;
		}
	}

	for (int i = 0; i < n; i++)	{
		int u, k; cin >> u >> k;
		for (int j = 0; j < k; j++)	{
			int v, w; cin >> v >> w;
			G[u][v] = w;
		}
	}

	dijkstra(0);

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

	return 0;
}

C++: #include<iostream>
#include<vector>
#include<queue>
using namespace std;
template< typename FirstType, typename SecondType >
struct PairComparator {
  bool operator()( const pair<FirstType, SecondType>& p1, const pair<FirstType, SecondType>& p2 ) const 
    {  
		return p1.first > p2.first;
    }
};
bool inMST(vector< std::pair<int,int> > & MST,int j) {
	for (int k=0;k<(int)MST.size();++k){
		if(j == MST[k].second)
			return true;
	}
	return false;
}
int main(){
	int n;
	cin >> n;
	vector<int> E(n*n,-1);
	vector<int> DPG(n,-1);
	vector< std::pair<int,int> > MST;
	for(int j=0;j<n;++j) {
		int u,k; 
		cin >> u >> k;
		for(int i=0;i<k;++i){
			int v,c;
			cin >> v >> c;
			E[u*n+v] = c;
		}
	}
	priority_queue<pair<int,pair<int,int> >,vector< pair<int,pair<int,int> > >,
		PairComparator<int,pair<int,int> > > r;

	int cost = 0;
	int i=0;
	MST.push_back(pair<int,int>(i,i));
	DPG[i] = 0;
	while((int)MST.size() < n) {
		int ii=i*n;
		for (int j=0;j<n;++j) {
			if (E[ii+j] >= 0) {
				pair<int,int> add = std::make_pair(i,j);
				if (!inMST(MST,add.second)){
					r.push(std::pair<int,std::pair<int,int> >(E[ii+j]+DPG[i],add));
				}
			}
		}
		pair<int,pair<int,int> > top;
		while (!r.empty()) {
			top = r.top();
			r.pop();
			if (!inMST(MST,top.second.second)){
				break;
			}
		}
		cost += top.first;
		MST.push_back(top.second);
		i = top.second.second;
		DPG[i] = top.first;
		for(int j=0;j<n;++j){
			if (DPG[j] < 0)continue;
			if (E[i*n+j] >= 0) {
				DPG[j] = std::min(DPG[j],DPG[i] + E[i*n+j]);
			}
		}
	}
	for (int j=0;j<n;++j) {
		cout << j << " " <<  DPG[j] << endl;
	}
}

C++: #include <iostream>
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 (1) {
        minv = INFTY;
        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]!=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;
        cout << i << " " << 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 <bits/stdc++.h>
using namespace std;

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

int n, M[MAX][MAX];

void dijkstra() {
    int u, minv;
    int color[MAX], d[MAX];
    for (int i = 0; i < n; i++) {
        color[i] = WHITE;
        d[i] = INFTY;
    }

    // 0 start
    d[0] = 0;
    while (true) {
        // choose u
        minv = INFTY;
        u = -1;
        for (int i = 0; i < n; i++)
        {
            if (color[i] != BLACK && d[i] < minv) {
                u = i;
                minv = d[i];
            }
        }

        if (u == -1) {
            break;
        }

        // move u
        color[u] = BLACK;

        // update distance
        for (int v = 0; v < n; v++){
            if (color[v] != BLACK && M[u][v] != INFTY) {
                if (d[v] > d[u] + M[u][v])
                    d[v] = d[u] + M[u][v];
            }
        }
    }
    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 u, k, c, 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();
}