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<iostream>
using namespace std;
#define MAX 100
#define White 1
#define Black 2
#define Red 3
#define Infinit 1e+8
struct Vertex {
	int weight,color, parent,totalweight;
};
int M[MAX][MAX];
int n;
Vertex v[MAX];
void search() {
	int pointer, min;
	for (int i = 0; i < n; i++) {
		if (i == 0) {
			v[i].weight = 0;
		}
		else {
			v[i].weight = Infinit;
		}
		v[i].color = White;
		v[i].parent = -1;
	}
	while (true) {
		min = Infinit;
		pointer = -1;
		for (int i = 0; i < n; i++) {
			if (v[i].color != Black && min > v[i].weight) {
				min = v[i].weight;
				pointer = i;
			}
		}
		if (min == Infinit) break;
		v[pointer].color = Black;
		for (int k = 0; k < n; k++) {
			if (M[pointer][k] != -1 && v[k].color != Black) {
				if (v[pointer].weight+M[pointer][k]<v[k].weight) {
					v[k].weight = v[pointer].weight+M[pointer][k];
					v[k].parent = pointer;
					v[k].color = Red;
				}
			}
		}

	}
	for (int i = 0; i < n; i++) {
		cout << i << " " << v[i].weight << endl;
	}
	
}
int main() {
	int u,k,v,c;
	cin >> n;
	for (int i = 0; i < n; i++) {
		for (int j = 0; j < n; j++) {
			M[i][j] = -1;
		}
	}
	for (int i = 0; i < n; i++) {
		cin >> u >> k;
		for (int i = 0; i < k; i++) {
			cin >> v >> c;
			M[u][v] = c;
		}
	}
	search();
}

C++: #include <bits/stdc++.h>
using namespace std;

int INF;
int n;
int es[100][100];

// sから各頂点への最短経路を求める
void dijkstra () {
  
  int minv;
  int d[100];

  // 0:未調査 1:調査中 2:調査完了
  int status[100];

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

  d[0] = 0;
  status[0] = 1;

  while (1) {
    minv = INF;
    int u = -1;
    for (int i = 0; i < n; i++) {
      if (d[i] < minv && status[i] != 2) {
        u = i;
        minv = d[i];
      }
    }
    if (u == -1) {
      break;
    }
    status[u] = 2;
    for (int v = 0; v < n; v++) {
      if (status[v] != 2 && es[u][v] != INF) {
        if (d[u] + es[u][v] < d[v]) {
          d[v] = d[u] + es[u][v];
          status[v] = 1;
        }
      }
    }
  }
  for (int i = 0; i < n; i++) {
    if (d[i] == INF) {
      cout << i << " -1" << endl;
    } else {
      cout << i << " " << d[i] << endl;
    } 
  }
}

int main() {
  
  cin >> n;

  INF = 2000000;

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

  // 入力を受け取る
  for (int i = 0; i < n; i++) {
    int u, k;
    cin >> u >> k;
    for (int j = 0; j < k; j++) {
      int v, c;
      cin >> v >> c;
      es[u][v] = c;
    }
  }

  // ダイクストラ法開始
  dijkstra();

  return 0;
}

C++: #include<iostream>
#include<cstring>
#include<algorithm>
using namespace std;

int x[1000][1000];
int y[1000];

int main() {
	memset(x, 1, sizeof(x));
	memset(y, 1, sizeof(y));
	int n, a, b, c, d;
	cin >> n;
	for (int i = 0; i < n; i++) {
		cin >> a >> b;
		for (int i = 0; i < b; i++) {
			cin >> c >> d;
			x[a][c] = d;
		}
	}
	y[0] = 0;
	for (int i = 0; i < n; i++) {
		for (int j = 0; j < n; j++) {
			for (int k = 0; k < n; k++) {
				y[k] = min(y[k], y[j] + x[j][k]);
			}
		}
	}
	for (int i = 0; i < n; i++) {
		cout << i << ' ' << y[i] << endl;
	}
	return 0;
}

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

int n,M[LEN][LEN];

void dijkstra()
{
    int minc;
    int d[LEN],color[LEN];

    for(int i=0;i<n;i++){
        d[i]=INF;
        color[i]=WHITE;
    }
    d[0]=0;
    color[0]=GRAY;
    while(1){
        minc=INF;
        int u=-1;
        for(int i=0;i<n;i++){
            if(d[i]<minc&& color[i]!=BLACK){
                minc=d[i]; u=i;
            }
        }
        if(u==-1) break;
        color[u]=BLACK;
        for(int i=0;i<n;i++){
            if(color[i]!=BLACK && M[u][i]!=INF){
                if(d[u]+M[u][i]<d[i]){
                    d[i]=d[u]+M[u][i];
                    color[i]=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,u,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();
    return 0;
}