Go: package main

import (
	"bufio"
	"container/heap"
	"fmt"
	"os"
	"strconv"
)

const NIL = -1

type Node struct {
	id     int
	weight int
}

func init() {
	sc.Split(bufio.ScanWords)
}

type NodeHeap []Node

func (h NodeHeap) Len() int           { return len(h) }
func (h NodeHeap) Less(i, j int) bool { return h[i].weight < h[j].weight }
func (h NodeHeap) Swap(i, j int)      { h[i], h[j] = h[j], h[i] }

func (h *NodeHeap) Push(x interface{}) {
	*h = append(*h, x.(Node))
}

func (h *NodeHeap) Pop() interface{} {
	old := *h
	n := len(old)
	x := old[n-1]
	*h = old[0 : n-1]
	return x
}

var sc = bufio.NewScanner(os.Stdin)

func scanInt() int {
	num, _ := strconv.Atoi(scanString())
	return num
}

func scanString() string {
	sc.Scan()
	return sc.Text()
}

func init() {
	sc.Split(bufio.ScanWords)
}

func main() {
	n := scanInt()

	route := make([][]Node, n)
	weight := make([]int, n)
	for i := 0; i < n; i++ {
		weight[i] = NIL
	}

	for i := 0; i < n; i++ {
		u := scanInt()
		k := scanInt()
		route[i] = make([]Node, k)
		for j := 0; j < k; j++ {
			route[u][j] = Node{id: scanInt(), weight: scanInt()}
		}
	}

	start := Node{id: 0, weight: 0}
	h := &NodeHeap{start}
	heap.Init(h)

	for h.Len() > 0 {
		node := heap.Pop(h).(Node)
		if weight[node.id] != NIL {
			continue
		}
		weight[node.id] = node.weight

		for _, nextNode := range route[node.id] {
			if weight[nextNode.id] != NIL {
				continue
			}
			nextNode.weight += node.weight
			heap.Push(h, nextNode)
		}
	}

	for i, w := range weight {
		fmt.Println(i, w)
	}
}

C++: //
//  main.cpp
//
//
//  Created by ???????????? on 2017/10/23.
//  Copyright ?? 2017 ????????????. All rights reserved.
//

#include <iostream>
#include <stdio.h>
#include <queue>
#include <algorithm>


#define n_max 100
#define WHITE 0
#define GRAY 1
#define BLACK 2
#define INFTY 1<<21

using namespace std;

int n, M[n_max][n_max], color[n_max], d[n_max], p[n_max];

void init(){
    int i, j, id, num, node;
    scanf("%d", &n);
    for(i = 0; i < n; i++){
        for(j = 0; j < n; j++){
            M[i][j] = INFTY;
        }
    }
    
    
    for(i = 0; i < n; i++){
        scanf("%d %d", &id, &num);
        for(j = 0; j < num; j++){
            scanf("%d", &node);
            scanf("%d", &M[id][node]);
        }
        color[i] = WHITE;
        d[i] = INFTY;
    }
}

void dijkstra(){
    //initializing
    d[0] = 0;
    p[0] = -1;
    
    priority_queue<pair<int, int>> PQ;
    
    PQ.push(make_pair(0, 0));
    
    int u;
    while(!PQ.empty()){
        int mincost = INFTY;
        //first weight, second idx
        pair<int, int> f= PQ.top(); PQ.pop();
        u = f.second;
        color[u] = BLACK;
        
        if(d[u] < f.first*(-1)) continue;
        
        for(int v = 0; v < n; v++){
            if((color[v] != BLACK) && (M[u][v] != INFTY)){
                if((d[u] + M[u][v]) < d[v]){
                    d[v] = M[u][v] + d[u];
//                    p[v] = u;
                    PQ.push(make_pair(d[v]*(-1), v));
                    color[v] = GRAY;
                }
            }
        }
    }
    for(int i = 0; i < n; i++){
        cout<<i<<" "<<d[i]<<endl;
    }
}

int main(int argc, const char * argv[]) {
    init();
    dijkstra();
    //    std::cout << "Hello, World!\n";
    return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
#define MAX 10005
#define INFTY INT_MAX

struct Node {
    int point;
    int weight;
    Node() {}
    Node(int p, int w) {
        point = p;
        weight = w;
    }
};

bool operator<(Node left, Node right) {
    return (left.weight > right.weight);
}

vector<vector<Node> > vec(MAX);
vector<Node> ve;
priority_queue<Node> pq;
Node node;
int n;

void dijkstra() {
    int d[MAX], color[MAX];
    for (int i = 0; i < n; i++) {
        d[i] = INFTY;
        color[i] = 0;
    }
    d[0] = 0;
    pq.push(Node(0, d[0]));
    while (!pq.empty()) {
        node = pq.top();
        pq.pop();
        int u = node.point;
        color[u] = 1;
        if (d[u] < node.weight)
            continue;
        for (int i = 0; i < vec[u].size(); i++) {
            int v = vec[u][i].point;
            int c = vec[u][i].weight;
            if (d[u] + c < d[v]) {
                d[v] = d[u] + c;
                pq.push(Node(v, d[v]));
            }
        }
    }
    for (int i = 0; i < n; i++) {
        cout << i << " " << d[i] << endl;
    }
}

int main(void) {
    cin >> n;
    int u, k;
    for (int i = 0; i < n; i++) {
        ve.clear();
        cin >> u >> k;
        while (k--) {
            cin >> node.point >> node.weight;
            ve.push_back(node);
        }
        vec[u] = ve;
    }

    dijkstra();
}

C++: #include <iostream>
#include <iomanip>
#include <vector>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <algorithm>
#include <cstdio>
#include <utility>
#include <string>
#include <cmath>
#include <cstdlib>
#include <cstring>

using namespace std;

typedef uint64_t u64;
typedef int64_t s64;
typedef uint32_t u32;
typedef int32_t s32;
typedef vector<s32> vs32;
typedef vector<u32> vu32;
typedef vector<s64> vs64;
typedef vector<u64> vu64;

const double PI=3.14159265358979323846;

#define MAX(x, y) ((x) < (y) ? (y) : (x))
#define MIN(x, y) ((x) > (y) ? (y) : (x))

#define rep(i, N) for(int i = 0; i < N; ++i)

#define CEIL(x, y) (((x) + (y) - 1) / (y))
#define MOD 1000000007ULL

class Graph
{
public:
    enum
    {
        WHITE = 0,
        GRAY = 1,
        BLACK = 2,
    };

    Graph() {}
    Graph(int n)
    : color(n, WHITE), M(n), d(n, INFTY)
    {}
    ~Graph() {}

    void dijkstra(int s)
    {
        d[s] = 0;
        priority_queue< pair<int, int> > pq;

        pq.push(make_pair(0, s));
        while (!pq.empty())
        {
            pair<int, int> du = pq.top(); pq.pop(); 

            int u = du.second;
            int minv = -du.first;

            color[u] = BLACK;

            if (d[u] < -minv) continue;

            for (auto dv : M[u])
            {
                int v = dv.first;
                int w = dv.second;
                if (color[v] != BLACK && d[v] > d[u] + w)
                {
                    d[v] = d[u] + w;
                    color[v] = GRAY;
                    pq.push(make_pair(-d[v], v));
                }
            }
        }
    }

    static const int INFTY = 1e9;
    vs32 color;
    vector< vector< pair<int, int> > > M;
    vs32 d;
};

int main()
{
    cin.tie(0);
    ios::sync_with_stdio(false);

    int n;
    cin >> n;

    Graph g(n);

    int u, v;
    int w;
    int c;
    rep (i, n)
    {
        cin >> u >> c;
        rep (j, c)
        {
            cin >> v >> w;
            g.M[u].emplace_back(v, w);
        }
    }

    g.dijkstra(0);
    rep (i, n)
    {
        cout << i << " " << g.d[i] << "\n";
    }
    return 0;
}