Go: package main

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

//make priority queue
type Item struct {
	id       int
	priority int // this state is priority and distans from start
	index    int
}

type PriorityQueue []*Item

func (pq PriorityQueue) Len() int { return len(pq) }

// we want the ascending-priority-queue.
// So we use less than here.
func (pq PriorityQueue) Less(i, j int) bool {
	return pq[i].priority < pq[j].priority
}

func (pq PriorityQueue) Swap(i, j int) {
	pq[i], pq[j] = pq[j], pq[i]
	pq[i].index = j
	pq[j].index = i
}

func (pq *PriorityQueue) Push(x interface{}) {
	n := len(*pq)
	item := x.(*Item)
	item.index = n
	*pq = append(*pq, item)
}

func (pq *PriorityQueue) Pop() interface{} {
	old := *pq
	n := len(old)
	item := old[n-1]
	item.index = -1 //for safety
	*pq = old[0 : n-1]
	return item
}

func (pq *PriorityQueue) update(dist int, id int) {
	for _, i := range *pq {
		if i.id == id {
			if i.priority > dist {
				i.priority = dist
			}
		}
	}
}

// the main code
func nextInt(sc *bufio.Scanner) int {
	sc.Scan()
	n, _ := strconv.Atoi(sc.Text())
	return n
}

func dikstra(dist *[][]int, n int) *[]int {
	// preparate priority queue
	inf := 1 << 30
	pq := make(PriorityQueue, n)
	shortests := make([]int, n)
	for i := 0; i < n; i++ {
		pq[i] = &Item{
			id:       i,
			priority: inf,
			index:    i,
		}

		shortests[i] = inf
	}
	pq[0].priority = 0
	shortests[0] = 0
	heap.Init(&pq)

	for pq.Len() > 0 {
		item := heap.Pop(&pq).(*Item)
		shortests[item.id] = item.priority
		for id, d := range (*dist)[item.id] {
			if d != -1 {
				pq.update(item.priority+d, id)
			}
		}
		heap.Init(&pq)
	}
	return &shortests
}

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

	// init
	n := nextInt(sc)
	dist := make([][]int, n)
	for i := 0; i < n; i++ {
		dist[i] = make([]int, n)
		for j := 0; j < n; j++ {
			dist[i][j] = -1
		}
	}

	// std Input
	for i := 0; i < n; i++ {
		u := nextInt(sc)
		k := nextInt(sc)
		for j := 0; j < k; j++ {
			v, c := nextInt(sc), nextInt(sc)
			dist[u][v] = c
		}
	}

	shortests := dikstra(&dist, n)
	for i, d := range *shortests {
		fmt.Printf("%d %d\n", i, d)
	}
}

C++: #include <iostream>
#include <cstdio>
#include <algorithm>
#include <cmath>
#include <climits>
#include <string>
#include <vector>
#include <utility>
#include <functional>
#include <stack>
#include <queue>
#include <map>
#include <set>
#include <cassert>

using namespace std;

typedef long long ll;
typedef pair<ll, ll> P;

const ll MOD = ll(1e9) + 7;
const ll INF = LLONG_MAX;
const ll MAX_N = ll(1e5) + 5;
const double EPS = 10e-8;
const double PI = 3.14159265359;

#define REP(i, n) for (ll i = 0; i < n; i++)
#define REPR(i, n) for (ll i = n; i >= 0; i--)
#define FOR(i, m, n) for (ll i = m; i < n; i++)

int dx[] = {1, 0, -1, 0}, dy[] = {0, 1, 0, -1};

struct UF {
    static const int MAX_N = 100000;
    int p[MAX_N];
    int r[MAX_N];

    void init(int n) {
        REP(i, n) {
            p[i] = i;
            r[i] = 0;
        }
    }
    int find(int x) {
        if (p[x] == x) return x;
        return p[x] = find(p[x]);
    }
    void unite(int x, int y) {
        x = find(x);
        y = find(y);
        if (x == y) return;
        if (r[x] < r[y]) swap(x, y);
        if (r[x] == r[y]) r[x]++;
        p[y] = x;
    }
    bool same(int x, int y) { return find(x) == find(y); }
};

ll n, d[100000];
vector<P> g[100000];

void dijkstra(ll s) {
    fill(d, d + n, INF);
    d[s] = 0;
    priority_queue<P> que;
    que.push({0, s});
    while (!que.empty()) {
        P p = que.top();
        que.pop();
        ll u = p.second;
        if (p.first > d[u]) continue;
        REP(i, g[u].size()) {
            ll v = g[u][i].first, cost = g[u][i].second;
            if (d[v] > d[u] + cost) {
                d[v] = d[u] + cost;
                que.push({d[v], v});
            }
        }
    }
}

int main() {
    cin >> n;
    REP(i, n) {
        ll from, k;
        cin >> from >> k;
        REP(j, k) {
            ll to, c;
            cin >> to >> c;
            g[from].push_back({to, c});
        }
    }
    dijkstra(0);
    REP(i, n) printf("%ld %ld\n",i,d[i]);
    return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;
typedef pair<int, int> P;
static const int Maxn = 10010;
static const int INFTY = (1 << 21);
static const int WHITE = 0;
static const int BLACK = 1;
vector <P> a[Maxn];
int n, d[Maxn], p[Maxn], color[Maxn];
struct cmp{
	bool operator()(P x, P y){
		return x.first > y.first;
	}
		
};
void dijkstra();
int main()
{
	int u, k, c, v;
	cin >> n;
	for(int i = 0; i < n; i++){
		cin >> u >> k;
		while(k--){
			cin >> v >> c;
			a[u].push_back(make_pair(v, c));
		}
	}
	dijkstra();
	return 0;
}
void dijkstra(){
	priority_queue <P, vector<P>, cmp> q;
	for(int i = 0; i < n; i++){
		d[i] = INFTY;
		color[i] = WHITE;
	} 
	d[0] = 0;
	q.push(make_pair(0,0));
	while(!q.empty()){
		P f = q.top(); q.pop();
		//printf("%d %d\n", f.first, f.second);
		int u = f.second;
		color[u] = BLACK;
		if(d[u] > f.first) continue;
		for(int i = 0; i < a[u].size(); i++){
			int v = a[u][i].first;
			if(color[v] == BLACK) continue;
			if(d[v] > d[u] + a[u][i].second){//
				d[v] = d[u] + a[u][i].second;
				q.push(P(d[v], v));
			} 
		}
	}
	for(int i = 0; i < n; i++) cout << i << ' ' << d[i] << endl;
}

C++: #include<iostream>
using namespace std;

static const int MAX = 1000;
static const int INFTY = (1<<21);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;


int n, M[MAX][MAX];

void dijkstra() {
    int minv;
    int d[MAX], color[MAX];

    for( int i = 0; i < n; i++ ) {
        d[i] = INFTY;
        color[i] = WHITE;
    }

    d[0] = 0;
    color[0] = GRAY;

    while(1) {
        minv = INFTY;
        int u = -1;
        for (int i = 0; i < n; i++) {
            if (minv  > d[i] && color[i] != BLACK) {
                u = i;
                minv = d[i];
            }
        }
        if (u == -1 ) {
            break;
        }
        color[u] = BLACK;
        for (int v = 0; v < n; v++) {
            if (d[v] > d[u] +M[u][v]) {
                d[v] = d[u] + M[u][v];
                color[v] = GRAY;
            }
        }
    }
    for (int i = 0; i < n; i++) {
        cout << i << " " << ( d[i] == INFTY ? -1 : d[i] ) << endl;
    }
}

int main(int argc, char const* argv[])
{
    cin >> n;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            M[i][j] = INFTY;
        }
    }

    int k, c, u, v;
    for (int i = 0; i < n; i++) {
        cin >> u >> k;
        for (int j = 0; j < k; j++) {
            cin >> v >> c;
            M[u][v] = c;
        }
    }

    dijkstra();
    return 0;
}