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>
#include <utility>
#include <vector>
#include <queue>
using namespace std;
#define INF 2400000000
long long int Min(long long int x,long long int y){
        return x>y?y:x;
}
int main(){
        int N;
        cin >> N;
        vector <vector <long long int> > adjancent(N,vector <long long int>(N,INF));
        for(int i=0 ; i<N ; i++ ){
                int n,degree,to,cost;
                cin >> n >> degree;
                for(int l=0 ; l<degree ; l++ ){
                        cin >> to >> cost;
                        adjancent[n][to]=cost;
                }
        }
        vector<long long int> dp(N,INF);
        dp[0]=0;
        bool sign=true;
        while(sign){
                sign=false;
                for(int now=0 ; now<N ; now++){
                        for(int i=0 ; i<N ; i++ ){
                                int tmp=dp[i];
                                dp[i]=Min(dp[i],dp[now]+adjancent[now][i]);
                                if(tmp!=dp[i])
                                        sign=true;
                        }
                }
        }
        for(int i=0 ; i<N ; i++ )
                cout <<i<<" "<<dp[i]<<endl;
        return 0;
}

C++: #include<iostream>
#include<vector>
#include<map>
#include<set>
#include<tuple>
#include<queue>
using namespace std;
#define int long long
vector<double> dijk(vector<tuple<int,int,double>> edge_list, int start){
        const int DJMAX = 100000;
        set<int> node_list;
        for(auto edge : edge_list){
                node_list.insert(get<0>(edge));
                node_list.insert(get<1>(edge));
        }
        int nodenum = *node_list.rbegin()+1;
        vector<vector<double>> cost_map(nodenum, vector<double>(nodenum, DJMAX));
        for(auto edge : edge_list){
                cost_map[get<0>(edge)][get<1>(edge)] = get<2>(edge);
                cost_map[get<1>(edge)][get<0>(edge)] = get<2>(edge);
        }
        vector<double> cost(nodenum,DJMAX);
        cost[start] = 0;
        vector<int> visited(nodenum,0);
        priority_queue<pair<int,int>> que;
        que.push(pair<double,int>(0,start));
        while(!que.empty()){
                int s = que.top().second;
                que.pop();
                visited[s] = 1;
                for(int j=0;j<nodenum;j++){
                        if(visited[j]==1) continue;
                        double nc = cost[s]+cost_map[s][j];
                        if(nc<cost[j]){
                                cost[j] = nc;
                                que.push(pair<double,int>(-cost[j],j));
                        }
                }
        }
        return cost;
}
signed main(){
        int n;
        cin >> n;
        vector<tuple<int, int, double>> edges;
        for(int i=0;i<n;i++){
                int vs, vn;
                cin >> vs >> vn;
                for(int j=0;j<vn;j++){
                        int vt,c;
                        cin >> vt >> c;
                        edges.push_back(tuple<int,int,double>(vs,vt,c));
                }
        }
        auto ans = dijk(edges, 0);
        for(int i=0;i<n;i++){
                cout << i << " " << ans[i] << endl;
        }
        return 0;
}

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

using namespace std;

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

    vector<vector<pair<int32_t, int32_t>>> A(n);

    for (int32_t i = 0; i < n; i++) {
        int32_t u, k;
        cin >> u >> k;

        for (int32_t j = 0; j < k; j++) {
            int32_t v, c;
            cin >> v >> c;
            A[u].push_back(make_pair(c, v));
        }
    }

    vector<int32_t> d(n, INT32_MAX);
    vector<bool> visited(n, false);
    priority_queue<pair<int32_t, int32_t>, vector<pair<int32_t, int32_t>>, greater<pair<int32_t, int32_t>>> q;
    q.push(make_pair(0, 0));

    while (!q.empty()) {
        int32_t u, d_u;
        tie(d_u, u) = q.top();
        q.pop();

        if (visited[u]) continue;
        visited[u] = true;

        d[u] = d_u;

        for (auto e : A[u]) {
            int32_t v, d_uv;
            tie(d_uv, v) = e;

            if (d[v] > d_u + d_uv) {
                q.push(make_pair(d_u + d_uv, v));
            }
        }
    }

    for (int32_t i = 0; i < n; i++) {
        cout << i << " " << d[i] << endl;
    }

    return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <algorithm>
using namespace std;
const int maxx=1010;
const int infinity=1<<30;
int A[maxx][maxx],d[maxx];
bool flag[maxx];
int n,a,b,c;
	
int main (){
	cin>>n;
	for(int i=0;i<n;i++){
		flag[i]=false;
		d[i]=infinity;
	}
	for(int i=0;i<n;i++){
		for(int j=0;j<n;j++){
			A[i][j]=infinity;
		}
	}
	for(int i=0;i<n;i++){
		cin>>a>>b;
		for(int j=0;j<b;j++){
			cin>>c>>A[a][c];
		}
	}
	d[0]=0;
	while(1){
		int minv=infinity,minj=-1;
		for(int i=0;i<n;i++){
			if(flag[i]==false && d[i]<minv){
				minv=d[i];
				minj=i;
			}
		}
		if(minv==infinity) break;
		flag[minj]=true;
		for(int i =0;i<n;i++){
			if(A[minj][i]!=infinity && flag[i]==false && d[i]>=d[minj]+A[minj][i]){
					d[i]=d[minj]+A[minj][i];
			}
		}
	}
	for(int i=0;i<n;i++) cout<<i<<" "<<(d[i]==infinity ? -1 : d[i])<<endl;
	
	return 0;

}