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
}

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) ([][]int, error) {
	adjacentMatrix := make([][]int, n)
	for i := 0; i < n; i++ {
		id, err := nextInt(sc)
		if err != nil {
			return nil, err
		}
		adjacentMatrix[id] = make([]int, n)
		for j := 0; j < n; j++ {
			adjacentMatrix[id][j] = -1
		}
		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][v] = c
		}
	}
	return adjacentMatrix, nil
}

func sssp(nodeStack []int, shortestList []ShortestInfo, adjacentMatrix [][]int) {
	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 [][]int) []Edge {
	adjacents := adjacentMatrix[currentNode]
	edges := []Edge{}
	for i, v := range adjacents {
		if v >= 0 {
			edges = append(edges, Edge{start: currentNode, end: i, weight: v})
		}
	}
	return edges
}

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

C++: // http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=ALDS1_12_A
// Graph II - Single Source Shortest Path II
// TODO: REVIEW

#define SUBMIT
//#define DEBUG

#include <utility>
#include <algorithm>
#include <iostream>
#include <iomanip>
#include <vector>
#include <limits>
#include <numeric>
#include <functional>
#include <set>
#include <cmath>
#include <cstring>
#include <climits>
#include <memory>
#include <queue>

using namespace std;
using ui64 = unsigned long long;
using i64 = long long;

enum class color_type {
    white,
    gray,
    black
};

const int INF = INT_MAX >> 1;
const ui64 MAX_N = 100000;
vector<pair<int, int>> adj[MAX_N];
int n;

int dijkstra() {
    // (cost, node) pair
    priority_queue<pair<int, int>> pq;
    color_type color[MAX_N];
    int d[MAX_N];

    for (int i = 0; i < n; ++i) {
        d[i] = INF;
        color[i] = color_type::white;
    }

    d[0] = 0;
    color[0] = color_type::gray;
    pq.push(make_pair(0, 0));

    while (!pq.empty()) {
        auto f = pq.top();
        pq.pop();
        int u = f.second;
        color[u] = color_type::black;

        // 最小値を取り出してそれが最短でなければ無視
        if (d[u] < -f.first) continue;

        for (int j = 0; j < adj[u].size(); ++j) {
            int v = adj[u][j].first;
            if (color[v] == color_type::black) continue;

            if (adj[u][j].second + d[u] < d[v]) {
                d[v] = d[u] + adj[u][j].second;
                pq.push(make_pair(-d[v], v));
                color[v] = color_type::gray;
            }
        }
    }

    for (int i = 0; i < n; ++i) cout << i << " " << (d[i] == INF ? -1 : d[i]) << endl;
}

int main() {
#ifdef SUBMIT
    auto& stream = cin;
#else
    string program_input_str = R"(5
0 3 2 3 3 1 1 2
1 2 0 2 3 4
2 3 0 3 3 1 4 1
3 4 2 1 0 1 1 4 4 3
4 2 2 1 3 3
)";
    stringstream stream(program_input_str);
#endif
    stream >> n;
    int u, v, c, degree;
    for (int i = 0; i < n; ++i) {
        stream >> u >> degree;
        for (int d = 0; d < degree; ++d) {
            stream >> v >> c;
            adj[u].emplace_back(make_pair(v, c));
        }
    }

#ifdef DEBUG
    for (int y = 0; y < n; ++y) {
        for (int x = 0; x < n; ++x) {
            cout << weight[y][x] << " ";
        }
        cout << endl;
    }
#endif

    dijkstra();
    return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define rep(i,n)   FOR(i,0,n)
#define pb emplace_back
typedef long long ll;
typedef pair<ll,ll> pint;

vector<pint> vp[10001];
ll d[10001];
ll INF=1000100010001000100;
int n;
int dijkstra(int st){
    priority_queue<pint,vector<pint>,greater<pint> > pq;
    rep(i,n) d[i]=INF;
    d[st]=0;
    pq.push(make_pair(0,st));
    while(!pq.empty()){
        pint pi=pq.top();pq.pop();
        int t=pi.second;
        if(d[t]<pi.first) continue;
        for(auto it:vp[t]){
            if(d[it.second]>d[t]+it.first){
                d[it.second]=d[t]+it.first;
                pq.push(make_pair(d[it.second],it.second));
            }
        }
    }
}
int main(){
    cin>>n;
    int u,k,v,c;
    rep(i,n){
        cin>>u>>k;
        rep(j,k){
            cin>>v>>c;
            vp[u].pb(c,v);
        }
    }
    dijkstra(0);
    rep(i,n){
        cout<<i<<" "<<d[i]<<endl;
    }
    return 0;
}

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

const int MAX_V = 10000;
const int INF=1e9;

int cost[MAX_V][MAX_V];
int d[MAX_V];
bool used[MAX_V];
int n;

void dijkstra(int s){
  REP(i,n) d[i]=INF;
  REP(i,n) used[i]=false;
  d[s]=0;
  while(true){
    int v=-1;
    REP(u,n)
      if(!used[u] && (v==-1 || d[u]<d[v]))
	v=u;
    if(v==-1) break;
    used[v]=true;
    REP(u,n) d[u]=min(d[u],d[v]+cost[v][u]);
  }
}

int main(){
  cin>>n;
  REP(i,n)REP(j,n) cost[i][j]=INF;
  REP(i,n){
    int u, k; cin>>u>>k;
    REP(j,k){
      int v,c;
      cin>>v>>c;
      cost[u][v]=c;
    }
  }
  dijkstra(0);
  REP(i,n){
    cout<<i<<" "<<d[i]<<endl;
  }
}