Go: package main

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

const (
	MAX_N      = 10000
	MAX_WEIGHT = 100000
)

type Edge struct {
	start  int
	end    int
	weight int
}

type ShortestInfo struct {
	edges    []Edge
	shortest int
}

type Neighbor struct {
	node   int
	weight int
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	n, err := nextInt(sc)
	if err != nil {
		panic(err)
	}

	shortestList := make([]ShortestInfo, n)
	for i := 1; i < n; i++ {
		shortestList[i] = ShortestInfo{edges: []Edge{}, shortest: MAX_N*MAX_WEIGHT + 1}
	}

	adjacentMatrix, err := createAdjacentMatrix(n, sc)
	if err != nil {
		panic(err)
	}

	sssp([]int{0}, shortestList, adjacentMatrix)
	for _, v := range shortestList {
		fmt.Printf("%d %d\n", v.getEnd(), v.shortest)
	}
}

func (si ShortestInfo) getEnd() int {
	if len(si.edges) == 0 {
		return 0
	} else {
		return si.edges[len(si.edges)-1].end
	}
}

func createAdjacentMatrix(n int, sc *bufio.Scanner) ([][]Neighbor, error) {
	adjacentMatrix := make([][]Neighbor, n)
	for i := 0; i < n; i++ {
		id, err := nextInt(sc)
		if err != nil {
			return nil, err
		}
		adjacentMatrix[id] = []Neighbor{}
		vertexNum, err := nextInt(sc)
		if err != nil {
			return nil, err
		}
		for j := 0; j < vertexNum; j++ {
			v, err := nextInt(sc)
			if err != nil {
				return nil, err
			}
			c, err := nextInt(sc)
			if err != nil {
				return nil, err
			}
			adjacentMatrix[id] = append(adjacentMatrix[id], Neighbor{v, c})
		}
	}
	return adjacentMatrix, nil
}

func sssp(nodeStack []int, shortestList []ShortestInfo, adjacentMatrix [][]Neighbor) {
	for len(nodeStack) > 0 {
		currentNode := nodeStack[0]
		nodeStack = nodeStack[1:]
		currentShortest := getShortest(currentNode, shortestList)
		adjacents := findAdjacents(currentNode, adjacentMatrix)
		for i := 0; i < len(adjacents); i++ {
			adj := adjacents[i]
			if currentShortest.shortest+adj.weight < getShortest(adj.end, shortestList).shortest {
				setShortest(adj.end, adj, currentShortest, shortestList)
				nodeStack = append(nodeStack, adj.end)
			}
		}
	}
}

func getShortest(node int, shortestList []ShortestInfo) ShortestInfo {
	return shortestList[node]
}

func setShortest(node int, edge Edge, currentShortest ShortestInfo, shortestList []ShortestInfo) {
	newEdges := make([]Edge, len(currentShortest.edges)+1)
	for i := 0; i < len(newEdges)-1; i++ {
		newEdges[i] = currentShortest.edges[i]
	}
	newEdges[len(newEdges)-1] = edge
	shortestInfo := ShortestInfo{edges: newEdges, shortest: currentShortest.shortest + edge.weight}
	shortestList[node] = shortestInfo
}

func findAdjacents(currentNode int, adjacentMatrix [][]Neighbor) []Edge {
	adjacents := adjacentMatrix[currentNode]
	edges := []Edge{}
	for _, neighbor := range adjacents {
		edges = append(edges, Edge{start: currentNode, end: neighbor.node, weight: neighbor.weight})
	}
	return edges
}

func nextInt(sc *bufio.Scanner) (int, error) {
	sc.Scan()
	return strconv.Atoi(sc.Text())
}

C++: #include<iostream>
#include <vector>
#include<algorithm>
#include <queue>
#define rep(i, a) for(int i=0; i<(int)(a); i++)
using namespace std;
int v, n, c, e,u,r,k;
const  long long int INF = (1<<21);
vector<pair<int, int>> ad[10000];
 void dijkstra() {
     priority_queue<pair<int, int>> p;
     int d[10000], co[10000];
     rep(i, n) {
         d[i] = INF;
         co[i] = 0;
     }
     d[0] = 0;
     p.push(make_pair(0, 0));
     co[0] = 1;
     while (!p.empty()) {
         pair<int, int> f = p.top();p.pop();
         int u = f.second;
         co[u] = 2;
         if (d[u] < f.first * (-1)) continue;
         rep(j, ad[u].size()) {
             int v = ad[u][j].first;
             if (co[v] != 2) {
                 if (d[v] > d[u] + ad[u][j].second) {
                     d[v] = d[u] + ad[u][j].second;
                     p.push(make_pair(d[v] * (-1), v));
                     co[v] = 1;
                 }
             }
         } 
     }
     rep(i, n) {
         cout << i << " " << (d[i] == INF ? -1 : d[i]) << endl;
     }
}
int main()
{
    cin >> n;
    rep(i, n) {
        cin >> u >> k;
        rep(j, k) {
            cin >> v >> c;
            ad[u].push_back(make_pair(v, c));
        }
    }
    dijkstra();
}

C++: #include <iostream>
#include <vector>
using namespace std;
int n;
/*
int dat[100][100];
int cost[100];
int done[100];

void prim(){
	for(int i=0;i<n;i++){
		cost[i]=1<<21;
		done[i]=0;
	}
	int s=0;	
	int next, ncost=1<<21;
	done[s]=1;
	cost[s]=0;
	while(1){
		ncost=1<<21;
		for(int j=0;j<n;j++){
			if(done[j]){
				for(int i=0;i<n;i++){
					if(dat[j][i]!=-1){
						if(cost[i]>=dat[j][i]&&!done[i]){
							cost[i]=dat[j][i];
						}
						if(ncost>cost[i]&&!done[i]){
							next=i;
							ncost=cost[i];
						}
					}
				}
			}
		}
//		cout<<"next:"<<next<<" cost:"<<cost[next]<<endl;
		done[next]=1;
		int flag=true;
		for(int i=0;i<n;i++){
			if(!done[i]) flag = false;
		}
		if(flag)
			return;
	}
}


void dijk(){
	for(int i=0;i<n;i++){
		cost[i]=1<<21;
		done[i]=0;
	}
	int s=0;	
	int next, ncost=1<<21;
	done[s]=1;
	cost[s]=0;
	while(1){
		ncost=1<<21;
		for(int j=0;j<n;j++){
			if(done[j]){
				for(int i=0;i<n;i++){
					if(dat[j][i]!=0){
						if(cost[i]>=dat[j][i]+cost[j]){
							cost[i]=dat[j][i]+cost[j];
						}
						if(ncost>cost[i]&&!done[i]){
							next=i;
							ncost=cost[i];
						}
					}
				}
			}
		}
//		cout<<"next:"<<next<<" cost:"<<cost[next]<<endl;
		done[next]=1;
		int flag=true;
		for(int i=0;i<n;i++){
			if(!done[i]) flag = false;
		}
		if(flag)
			return;
	}
}
*/

vector<vector<int> > dat;
int cost[10000];
int done[10000];

void dijk2(){
	for(int i=0;i<n;i++){
		cost[i]=1<<21;
		done[i]=0;
	}
	int s=0;	
	int next, ncost=1<<21;
	done[s]=1;
	cost[s]=0;
	while(1){
		ncost=1<<21;
		for(int j=0;j<n;j++){
			if(done[j]){
				for(int i=0;i<n;i++){
					if(dat[j][i]!=0){
						if(!done[i]){
							if(cost[i]>=dat[j][i]+cost[j]){
								cost[i]=dat[j][i]+cost[j];
							}
							if(ncost>cost[i]){
								next=i;
								ncost=cost[i];
							}
						}
					}
				}
			}
		}
//		cout<<"next:"<<next<<" cost:"<<cost[next]<<endl;
		done[next]=1;
		int flag=true;
		for(int i=0;i<n;i++){
			if(!done[i]) flag = false;
		}
		if(flag)
			return;
	}
}



int main(){
	int num, from, dist, c;
	cin>>n;	
	dat.reserve(n);
	for(int i=0;i<n;i++){
		vector<int> d(n);
		dat.push_back(d);
	}
	for(int i=0;i<n;i++){
		cin>>from>>num;
		for(int j=0;j<num;j++){
			cin>>dist>>c;
			dat[from][dist]=c;
		}
	}
	dijk2();
	for(int i=0;i<n;i++){
		cout<<i<<" "<<cost[i]<<endl;
	}
	return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i=0;i<(n);i++)

const long long INFF = 1e18;

const int MAX_N = 11000;
using TYPE = long long; // ?????¢???????????\??????
vector<pair<int, TYPE> > G[MAX_N];

vector<TYPE> A_star(int start){
	vector<TYPE> dist(MAX_N, INFF);
	dist[start] = 0;//dist[i] :=???start->i?????§??????????????¢
	priority_queue<pair<TYPE, int>, vector<pair<TYPE, int> >, greater<pair<TYPE, int> > >  que;
	que.push(make_pair(0, start));
	while(!que.empty()){
		TYPE cost; int u;//????????§???????????£????????? ?????¨?????????
		cost = que.top().first, u = que.top().second;
		que.pop();
		// if(dist[u] < cost) continue;
		for (auto tmp : G[u]){
			int v = tmp.first; TYPE time = tmp.second;//??£??\???????????? ?????????????????§????????????
			if(dist[v] > dist[u] + time){//u->v
				dist[v] = dist[u] + time;
				auto h = 0; // ??´???????????§?????¨??????
				// printf("%f\n", h);
				que.push(make_pair(dist[v] + h, v));
			}
		}
	}
	return dist;
}

int main(void) {
	int n; cin >> n;
	rep(i, n) {
		int u, k; cin >> u >> k;
		vector<int> v(k), c(k);
		rep(i, k) cin >> v[i] >> c[i];
		rep(i, k) G[u].push_back(make_pair(v[i], c[i])), G[v[i]].push_back(make_pair(u, c[i]));
	}
	auto dist = A_star(0);
	rep(i, n) printf("%d %d\n", i, dist[i]);
	return 0;
}