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++: #include <bits/stdc++.h>
#define FOR(i, a, b) for (int i = (a), i##_max = (b); i < i##_max; ++i)
#define RFOR(i, a, b) for (int i = (b)-1, i##_min = (a); i >= i##_min; --i)
#define REP(i, n) for (int i = 0, i##_len = (n); i < i##_len; ++i)
#define RREP(i, n) for (int i = (n)-1; i >= 0; --i)
#define ALL(obj) (obj).begin(), (obj).end()

using namespace std;
using vi = vector<int>;
using vd = vector<double>;
using pi = pair<int, int>;
using i64 = int64_t;

constexpr int INF = 1 << 30;
constexpr int MOD = 1000000007;

template <typename T>
void print(vector<T> &v) {
  REP(i, v.size()) {
    if (i) cout << " ";
    cout << v[i];
  }
  cout << endl;
}

void dijkstra(vector<vector<pi>> &adj) {
  auto n = adj.size();
  priority_queue<pi> PQ;
  vi d(n, INF);
  vector<bool> visited(n, false);
  d[0] = 0;
  PQ.push(make_pair(0, 0));
  while (!PQ.empty()) {
    auto f = PQ.top();
    PQ.pop();
    auto u = f.second;
    visited[u] = true;
    if (d[u] < -f.first) continue;
    REP(i, adj[u].size()) {
      auto v = adj[u][i].first;
      auto new_cost = d[u] + adj[u][i].second;
      if (!visited[v] && new_cost < d[v]) {
        d[v] = new_cost;
        PQ.push(make_pair(-d[v], v));
      }
    }
  }
  REP(i, n) cout << i << " " << (d[i] == INF ? -1 : d[i]) << endl;
}

int main() {
  int n;
  cin >> n;
  vector<vector<pi>> adj(n);
  int k, c, u, v;
  REP(i, n) {
    cin >> u >> k;
    REP(j, k) {
      cin >> v >> c;
      adj[u].push_back(make_pair(v, c));
    }
  }
  dijkstra(adj);
}

C++: #include <iostream>
#include <algorithm>
#include <vector>
#include <deque>
#include <queue>
#include <list>
#include <stack>
#include <string>
#include <tuple>
#include <functional>
#include <numeric>
#include <cmath>
#include <iomanip>
#include <map>
#include <random>
#include <cstdlib>
#define INT_MAX 2147483647
#define INT_MIN -2147483646
#define Loop(i, n) for(int i = 0; i < (int)n; i++)
#define Loop1(i, n) for(int i = 1; i <= (int)n; i++)
#define Loopr(i, n) for(int i = (int)n - 1; i >= 0; i--)
#define Loopr1(i, n) for(int i = (int)n; i >= 1; i--)
using namespace std;
typedef long long int ll;
typedef vector<int> vi;
typedef vector<vector<int>> vvi;

static const int N = 105;

struct vertex {
	int id;
	int p;
	int d;
	bool operator<(const vertex & another) const {
		return (d != another.d ? d>another.d : id>another.id);
	}
};

struct edge {
	int end;
	int w;
};

int main() {
	int n;
	cin >> n;
	vector<vector<edge>> E(N);
	Loop(i, n) {
		int u, k;
		cin >> u >> k;
		Loop(i, k) {
			int v, c;
			cin >> v >> c;
			E[u].push_back({ v,c });
		}
	}
	//
	priority_queue<vertex> pq;
	vi color(N, 0), dist(N, 0);
	pq.push({ 0,-1,0 });
	while (pq.size() > 0) {
		vertex v = pq.top();
		pq.pop();
		if (color[v.id] == 1) continue;
		dist[v.id] = v.d;
		color[v.id] = 1;
		Loop(j, E[v.id].size()) {
			pq.push({ E[v.id][j].end, v.id, dist[v.id] + E[v.id][j].w });
		}
	}
	Loop(i, n) {
		cout << i << " " << dist[i] << endl;
	}
	return 0;
}

C++: #include<iostream>
#include<cstdio>
#include<string>
#include<algorithm>
#include<cstring>
#include<vector>
#include<queue>
using namespace std;
#define int(x) int x; scanf("%d",&x)
#define input(x) scanf("%d",&x)
#define rep(x,n) for(int x = 0; x < n; x++)
#define _br printf("\n")
#define INF 2000000000

vector<pair<int,int> > PathList[10000];
int d[10000];
bool complete[10000];

void dijkstra(int n,vector<pair<int,int> > PathList[]){
    priority_queue<pair<int,int> > PQ;
    
    rep(i,n){
        d[i] = INF;
        complete[i] = false;
    }
    d[0] = 0;
    PQ.push(make_pair(-d[0],0));
    int count = 0;
    
    while (count != n) {
        //select
        int mindi;
        while (1) {
            if (!complete[PQ.top().second]) {
                mindi = PQ.top().second;
                PQ.pop();
                break;
            }
            PQ.pop();
        }
        
        complete[mindi] = true;
        count++;
        
        //update
        rep(i,PathList[mindi].size()){
            if (PathList[mindi][i].second + d[mindi] < d[PathList[mindi][i].first]) {
                d[PathList[mindi][i].first] = PathList[mindi][i].second + d[mindi];
                PQ.push(make_pair(-(PathList[mindi][i].second + d[mindi]),PathList[mindi][i].first));
            }
        }
    }
}


int main(){
    int(n);
    rep(i,n){
        int(k);int(num);
        rep(j,num){
            int(s);int(t);
            PathList[i].push_back(make_pair(s,t));
        }
    }
    
    dijkstra(n,PathList);
    
    rep(i,n){
        printf("%d %d\n",i,d[i]);
    }
    
    return 0;
}

C++: #include <iostream>
#include <queue>
using namespace std;
#define MAX 10000
#define INFTY 100000000
#define WHITE 1
#define GRAY 0
#define BLACK -1

vector<pair<int,int> > Adj[MAX];
priority_queue<pair<int,int> >Queue;
int d[MAX];
int c[MAX];

void init(int n) {
    int i;
    
    for(i = 0; i < n; i++){
        d[i] = INFTY;
        c[i] = WHITE;
    }
    
    d[0] = 0;
    c[0] = GRAY;  
    Queue.push(make_pair(0,0));
}

void sssp(int n){
    int u, i, v, tmp;
    
    init(n);
    
    while(!Queue.empty()){
        pair<int,int> f = Queue.top();
        Queue.pop();
        u = f.second;
        c[u] = BLACK;
        
        if(d[u] < f.first * -1) continue;
        for(i = 0; i < Adj[u].size(); i++){
            v = Adj[u][i].first;
            if(c[v] == BLACK) continue;
            if(d[v] > d[u] + Adj[u][i].second){
                d[v] = d[u] + Adj[u][i].second;
                tmp = d[v] * -1;
                Queue.push(make_pair(tmp, v));
                c[v] = GRAY;
            }
        }
    }
    
    for(i = 0; i < n; i++){
        cout << i << " " << ( d[i] == INFTY ? -1 : d[i] ) << endl;
    }
}

int main(){
    int n, m, l, a, b, i, j;
    
    cin >> n;
    
    for(i = 0; i < n; i++){
        cin >> l >> m;
        for(j = 0; j < m; j++){
            cin >> a >> b;
            Adj[l].push_back(make_pair(a, b));
        }
    }
    
    sssp(n);
    
    return 0;
}