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 <limits>

#define FOR(i,a,b) for (int i = (a); i < (b); ++i)

constexpr int MAXN = 100;
constexpr int MAXINT = std::numeric_limits<int>::max();


int G[MAXN][MAXN];
int D[MAXN];
int C[MAXN];
int P[MAXN];
int n;

int main() {
    std::cin >> n;
    FOR(i, 0, n)
    FOR(j, 0, n)
    {
        G[i][j] = MAXINT;
    }

    FOR(i, 0, n){
        int id, e;
        std::cin >> id >> e;
        FOR(i, 0, e) {
            int v, c;
            std::cin >> v >> c;
            G[id][v] = c;
        }
    }

    FOR(i, 0, n) D[i] = MAXINT;

    int r = -1;
    D[0] = 0;
    while (true) {
        int mincost = MAXINT;
        int t;
        for (int i = 0; i < n; i++) {
            if ((C[i] == 0)  && (D[i] < mincost)) {
                mincost = D[i];
                t = i;
            }
        }

        if (mincost == MAXINT) {
            break;
        }

        C[t] = 1;
        P[t] = r;

        for (int i = 0; i < n; i++) {
            if ((C[i] == 0) && (G[t][i] != MAXINT) && ((D[t] + G[t][i]) < D[i])) {
                D[i] = D[t] + G[t][i];
            }
        }
        r = t;
    }
    FOR(i, 0, n) {
        std::cout << i << " " << D[i] << std::endl;
    }
}

C++: #include <algorithm>
#include <iostream>
#include <string>
using namespace std;
static const int NMAX = 100;
#define INF (1 << 30)
int ADJ[NMAX][NMAX];

int main() {
  int n;
  cin >> n;
  for (int i = 0; i < n; i++)
    for (int j = 0; j < n; j++)
      ADJ[i][j] = INF;

  for (int i = 0; i < n; i++) {
    int id, nn;
    cin >> id  >> nn;
    for (int j = 0; j < nn; j++) {
      int to, weight;
      cin >> to >> weight;
      ADJ[id][to] = weight;
    }
  }

  bool visited[n];
  int dist[n];

  // add node 0
  for (int i = 0; i < n; i++) {
    dist[i] = ADJ[0][i];
    visited[i] = false;
  }
  visited[0] = true;
  dist[0] = 0;

  while (true) {
    int minnode = -1;
    int mincost = INF;
    // find nearest node
    for (int i = 0; i < n; i++) {
      if (visited[i] == false && dist[i] < mincost) {
        minnode = i;
        mincost = dist[i];
      }
    }
    if (minnode == -1)
      break;

    // add node
    visited[minnode] = true;

    // update dist
    for (int i = 0; i < n; i++) {
      if (visited[i] == false)
        dist[i] = min(dist[i], dist[minnode] + ADJ[minnode][i]);
    }
  }

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

C++: a

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;
    }
}

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>
#include <algorithm>
#define N 100
#define INF (1<<30)
using namespace std;

int n, M[N][N], d[N], color[N] = {0};

void Dijk(int s) {
	int min;
	for (int i = 0;i < n;i++) d[i] = INF;
	d[s] = 0;
	color[s] = 1;
	while (true) {
		int u=-1;
	    min = INF;
		for (int i = 0;i < n;i++) {
			if (color[i] != 2 && d[i] < min)
			{
				u = i;
				min = d[u];
			}
		}

		if (u==-1) break;

		color[u] = 2;

		for (int v = 0;v < n;v++) {
			if (color[v] != 2 && M[u][v] != INF)
				if (d[v] > d[u] + M[u][v]) {
					d[v] = d[u] + M[u][v];
					color[v] = 1;
				}
		}
	}

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

}

int main() {

	for (int i = 0;i < N;i++)
		for (int j = 0;j < N;j++) M[i][j] = INF;

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

	Dijk(0);

}

C++: ///
// File:  alds1_12_b.cpp
// Author: ymiyamoto
//
// Created on Wed Oct 18 21:59:56 2017
//

#include <cstdint>
#include <iostream>

using namespace std;
#define SIZE 100
static int64_t graph[SIZE][SIZE];
static int64_t costs[SIZE];
static bool visited[SIZE];

static void dikstra(uint32_t n)
{
  costs[0] = 0;

  while (true) {
    int32_t min_index = -1;
    int64_t min_cost = INT32_MAX;

    for (uint32_t i = 0; i < n; i++) {
      if (!visited[i] && costs[i] < min_cost) {
        min_cost = costs[i];
        min_index = i;
      }
    }

    if (min_index == -1) break;

    visited[min_index] = true;

    for (uint32_t i = 0; i < n; i++) {
      if (graph[min_index][i] != -1) {
        if (costs[min_index] + graph[min_index][i] < costs[i]) {
          costs[i] = costs[min_index] + graph[min_index][i];
        }
      }
    }
  }
}

int32_t main()
{
  uint32_t n;
  cin >> n;

  for (uint32_t i = 0; i < n; i++) {
    for (uint32_t j = 0; j < n; j++) {
      graph[i][j] = -1;
    }
    costs[i] = INT32_MAX;
  }

  for (uint32_t i = 0; i < n; i++) {
    uint32_t id, k;
    cin >> id >> k;
    for (uint32_t j = 0; j < k; j++) {
      int64_t v, c;
      cin >> v >> c;
      graph[id][v] = c;
    }
  }

  dikstra(n);

  for (uint32_t i = 0; i < n; i++) {
    cout << i << " " << costs[i] << endl;
  }

  return 0;
}