Go: package main

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

var scanner = bufio.NewScanner(os.Stdin)

func nextString() string {
	scanner.Scan()
	return scanner.Text()
}

func nextInt() int {
	n, err := strconv.Atoi(nextString())
	if err != nil {
		fmt.Printf("strconv.Atoi failed: %v\n", err)
	}
	return n
}

var infty = 1000000000

type DirectedGraphNodeID int

type DirectedGraphNode struct {
	key         DirectedGraphNodeID
	adjacents   []*DirectedGraphNode
	costs       []int
	distance    int
	predecessor *DirectedGraphNode
}

func newDirectedGraph(nNodes int) *DirectedGraph {
	graph := DirectedGraph{}
	graph.nodes = make([]*DirectedGraphNode, nNodes)
	for i := 0; i < nNodes; i++ {
		node := DirectedGraphNode{}
		node.key = DirectedGraphNodeID(i)
		node.distance = infty
		graph.nodes[i] = &node
	}
	return &graph
}

type DirectedGraph struct {
	nodes []*DirectedGraphNode
}

func (g *DirectedGraph) setAdjacency(i, j DirectedGraphNodeID, cost int) {
	g.nodes[i].adjacents = append(g.nodes[i].adjacents, g.nodes[j])
	g.nodes[i].costs = append(g.nodes[i].costs, cost)
}

func (g *DirectedGraph) print() {
	for i := 0; i < len(g.nodes); i++ {
		node := g.nodes[i]
		key := node.key
		strings := []string{strconv.Itoa(int(key)), strconv.Itoa(node.distance)}
		for j := 0; j < len(node.adjacents); j++ {
			nodeJ := fmt.Sprintf("(%v, %v)", node.adjacents[j].key, node.costs[j])
			strings = append(strings, nodeJ)
		}
		fmt.Printf("%v\n", strings)
	}
}

func (g *DirectedGraph) relaxEdge(l, r *DirectedGraphNode, w int) {
	if r.distance > l.distance+w {
		// fmt.Printf("%v -> %v, %v\n", l.key, r.key, l.distance+w)
		r.distance = l.distance + w
		r.predecessor = l
	}
}

func main() {
	scanner.Split(bufio.ScanWords)

	nNodes := nextInt()
	graph := newDirectedGraph(nNodes)

	for i := 0; i < nNodes; i++ {
		iNode := DirectedGraphNodeID(nextInt())
		nAdjacent := nextInt()
		for j := 0; j < nAdjacent; j++ {
			jNode := DirectedGraphNodeID(nextInt())
			cost := nextInt()
			graph.setAdjacency(iNode, jNode, cost)
		}
	}

	graph.nodes[0].distance = 0
	for iNode := 0; iNode < nNodes; iNode++ {
		for iLeft := 0; iLeft < len(graph.nodes); iLeft++ {
			nodeLeft := graph.nodes[iLeft]
			for iRight := 0; iRight < len(nodeLeft.adjacents); iRight++ {
				nodeRight := nodeLeft.adjacents[iRight]
				cost := nodeLeft.costs[iRight]
				graph.relaxEdge(nodeLeft, nodeRight, cost)
			}
		}
	}

	// graph.print()

	for iNode := 0; iNode < len(graph.nodes); iNode++ {
		node := graph.nodes[iNode]
		fmt.Println(node.key, node.distance)
	}
}

C++: #include <cstdio>
#include <queue>
#include <utility>
using namespace std;
static const int INFTY = (1 << 21);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n;
vector<pair<int, int>> adj[100];
int *d;

void dijkstra() {
    priority_queue<pair<int, int>> PQ;
    int d[n], color[n];

    for (int i = 0; i < n; i++) {
        d[i] = INFTY;
        color[n] = WHITE;
    }
    d[0] = 0;
    PQ.push(make_pair(0, 0));

    while (!PQ.empty()) {
        pair<int, int> f = PQ.top();
        PQ.pop();

        int u = f.second;
        color[u] = BLACK;

        if (d[u] < f.first * (-1)) { continue; }

        for (int j = 0; j < adj[u].size(); j++) {
            int v = adj[u][j].first;
            if (color[v] == BLACK) { continue; }
            if (d[u] + adj[u][j].second < d[v]) {
                d[v] = d[u] + adj[u][j].second;
                // printf("d[%d] = %d\n", v, d[v]);
                PQ.push(make_pair(d[v] * (-1), v));
                color[v] = GRAY;
            }
        }
    }
    
    for (int i = 0; i < n; i++) {
        printf("%d %d\n", i, d[i]);
    }
}

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

    // adj = new vector<pair<int, int>>[n];

    for (int i = 0; i < n; i++) {
        int u, k;
        scanf("%d %d", &u, &k);
        for (int j = 0; j < k; j++) {
            int v, c;
            scanf("%d %d", &v, &c);
            adj[u].push_back(make_pair(v, c));
        }
    }

    dijkstra();

    return 0;
}

C++: #include <iostream>
using namespace std;
int n;
static const int MAX = 100;
static const int INF = (1 << 21);
int M[MAX][MAX];
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;


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[]

    while(1){
        minv = INF;
        int u = -1;

        for (int i = 0; i < n; i++){
            if (minv > d[i] && color[i] != BLACK){
                minv= d[i];
                u = i;
            }
        }

        if (u == -1){ //全部探索済み
            break;
        }

        color[u] = BLACK;
        for (int i = 0; i < n; i++){
            if (color[i] != BLACK && d[i] > M[u][i] != INF){
                if (d[i] > d[u] + M[u][i]){
                    color[i] = GRAY;
                    d[i] = d[u] + M[u][i];
                }
            }
        }
    }
    for (int i = 0; i < n; i++){
            cout << i << " ";
            if (d[i] == INF){
                cout << -1 << endl;
            }else{
                cout << d[i] << endl;
            }
            
        }
}

int main(void){
    int tmp;

    cin >> n;

    for (int i = 0; i < n; i++){
        for (int j = 0; j < n; j++){
            M[i][j] = INF;
        }
    }

    int u, k;
    int v, c;
    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();

    return 0;
}

C++: #include <iostream>
#include <vector>

using namespace std;

int d[100];

int main(void)
{
    int n;
    cin >> n;

    int graph[n][n];

    for (int i = 0; i < n; i++)
        for (int j = 0; j < n; j++)
            graph[i][j] = -1;

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

    for (int i = 0; i < n; i++)
        d[i] = 100000000;
    d[0] = 0;

    vector<int> queue;
    for (int i = 0; i < n; i++)
        queue.push_back(i);

    while (!queue.empty()) {
        int u = queue[0];
        size_t j = 0;
        for (size_t i = 0; i < queue.size(); i++)
            if (d[queue[i]] < d[u]) {
                u = queue[i];
                j = i;
            }
        queue.erase(queue.begin() + j);

        for (int v = 0; v < n; v++)
            if (graph[u][v] > 0)
                if (d[v] > d[u] + graph[u][v])
                    d[v] = d[u] + graph[u][v];
    }

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

    
    return 0;
}

C++: #include<stdio.h>
#include<limits.h>
#define NIL -1
static const int MAX = 1005;
static const int INFTY = (1<<21);

main(){
  int n, i, j, v, c, u, k, minV;
  int M[MAX][MAX], A[MAX], key[MAX], p[MAX];
  /*your code*/

  scanf("%d", &n);
  for ( i = 0; i< n; i++ ){
    for ( j = 0; j < n; j++ ){
      M[i][j] = INFTY;
    }
  }

  for ( i = 0; i < n; i++ ){
    scanf("%d %d", &u, &k);
    for ( j = 0; j < k; j++ ){
      scanf("%d %d", &v, &c);
      M[u][v] = c;
    }
  }

  /*your code*/
  for(i = 0; i < n; i++){
    key[i] = INT_MAX;
    p[i] = NIL;
    A[i] = NIL;
  }
  
  key[0]=0;
  
  while(1){
    
    u = NIL;
    
    minV = INT_MAX;
    
    for(i = 0;  i < n; i++){
      
      if(key[i] < minV && A[i] == NIL){
	
	u = i;
	
	minV = key[i];
	
      }
      
    }  
    if(u == NIL)break;
    
    A[u] = u; 
    
    for(v = 0; v < n; v++){
      if((M[u][v]+key[u]) < key[v] && A[v] == NIL){
	key[v] = (M[u][v]+key[u]);
	p[v] = u;
      }
    }
  }
  
  for ( i = 0; i < n; i++ ){
    printf("%d %d\n", i, (key[i]==INFTY?-1:key[i]));
  }

  return 0;

}