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 <bits/stdc++.h>
using namespace std;

const int MAX=105;
int state[MAX],N,D[MAX];
vector<pair<int,int>> S[MAX];
priority_queue<pair<int,int>> Q;

void dijkstra(){
    int cnt=1;
    for(int i=0;i<N;i++){
        state[i]=0;
        D[i]=100000000;
    }
    state[0]=1;
    D[0]=0;
    for(int i=0;i<S[0].size();i++){
        Q.push(make_pair(-S[0][i].second,S[0][i].first));
        D[S[0][i].first]=min(D[S[0][i].first],D[0]+S[0][i].second);
    }
    while(1){
        int a=Q.top().second;
        cout<<a<<endl;
        if(state[a]==0){
            Q.pop();
            state[a]=1;
            cnt++;
            for(int i=0;i<S[a].size();i++){
                if(state[S[a][i].first]==0){
                    Q.push(make_pair(-S[a][i].second,S[a][i].first));
                    D[S[a][i].first]=min(D[S[a][i].first],D[a]+S[a][i].second);
                }
            }
        }
        else Q.pop();
        if(cnt==N) break;
    }
    return;
}


int main(){
    
    cin>>N;
    for(int i=0;i<N;i++){
        int l,a;cin>>l>>a;
        for(int j=0;j<a;j++){
            int b,c;cin>>b>>c;
            S[i].push_back(make_pair(b,c));
        }
    }
    dijkstra();
    for(int i=0;i<N;i++){
        cout<<i<<" "<<D[i]<<endl;
    }
}

C++: #include <iostream>
#define rep(i,N) for(int i = 0; i<(int)(N); i++)
#define REP(i,k,N) for(int i = k; i<(int)(N); i++)
#define INF 100000+1
typedef long long ll;
using namespace std;

int main(){
        int n;
        cin >> n;
        int d[100][100];
        rep(i,100) rep(j,100) d[i][j]=INF;

        int u,k,v,c;
        rep(i,n){
                cin >> u >>k;
                rep(j,k){
                        cin >> v >> c;
                        d[u][v] = c;
                }
        }

        ll l[100];
        rep(i,n) l[i]=INF*n;
        l[0]=0;
        bool update = true;
        while(update) {
                update  = false;
                rep(from,n) {
                        if(l[from] == INF*n) continue;
                        rep(to,n){
                                if(from == to) continue;

                                if(l[to] > l[from]+d[from][to]) {
                                        update = true;
                                        l[to] = l[from]+d[from][to];
                                }

                        }
                }
        }
        rep(i,n){
                cout << i << " " << l[i] << endl;
        }

        return 0;
}

C++: #include<iostream>
#include<vector>
#include<algorithm>
#define MAX_V 100
#define INF 1e9
using namespace std;
int cost[MAX_V][MAX_V];
int d[MAX_V];
bool used[MAX_V];
int V;
void dijkstra(int s) {
	for (int i = 0; i < V; i++) {
		d[i] = INF;
		used[i] = false;
	}
	d[s] = 0;
	while (true) {
		int v = -1;
		for (int u = 0; u < V; u++) {
			if (!used[u] && ((v == -1) || d[u] < d[v])) {
				v = u;
			}
		}
		//全ての頂点が到達済み
		if (v == -1) {
			break;
		}
		//集合に新たに頂点を追加
		used[v] = true;
		for (int u = 0; u < V; u++) {
			if (cost[v][u] != -1) {
				d[u] = min(d[u], d[v] + cost[v][u]);
			}
		}
	}
}

int main() {   
	cin >> V;
	for (int i = 0; i < V; i++) {     
		for (int j = 0; j < V; j++) { 
			cost[i][j] = -1;               
		}                                 
	}                                      
	
	for (int i = 0; i < V; i++) {
		int u;
		cin >> u;
		int k;
		cin >> k;
		for (int j = 0; j < k; j++) {
			int v;
			cin >> v;
			int c;
			cin >> c;
			cost[u][v] = c;
		}
	}
	dijkstra(0);

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