Go: package main

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

const BIG_COST = 200000

type Path struct {
	node int
	cost int
}

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

	nNodes := scanInt(sc)

	// 各頂点につながる頂点一覧を得るための隣接リスト
	graph := make([][]Path, nNodes)

	for i := 0; i < nNodes; i++ {
		u := scanInt(sc)
		k := scanInt(sc)
		graph[i] = make([]Path, k)
		for d := 0; d < k; d++ {
			graph[u][d] = Path{
				node: scanInt(sc),
				cost: scanInt(sc),
			}
		}
	}

	// 0 から各頂点への最小コストを保存する配列
	minCosts := make([]int, nNodes)

	minCosts[0] = 0
	for i := 1; i < nNodes; i++ {
		minCosts[i] = BIG_COST
	}

	// 各頂点が調査済みかどうかを保持する配列
	checked := make([]bool, nNodes)

	// 最小コストのパスを高速に取得するためのヒープ。
	// コストが小さいものほどルートに来るようにする。
	heap := NewHeap(func(a, b Path) bool {
		return a.cost < b.cost
	})

	heap.insert(Path{node: 0, cost: 0})
	for heap.size > 0 {
		u := heap.extractMax()

		// 隣接行列を使っていた時とは違い、ヒープには
		// 同じノードへのパスが複数含まれうる。そのため既によりコストの低い
		// パスが見つかっている場合は無視する。
		if minCosts[u.node] < u.cost {
			continue
		}

		checked[u.node] = true

		for _, v := range graph[u.node] {
			cost := v.cost + u.cost
			if !checked[v.node] && cost < minCosts[v.node] {
				minCosts[v.node] = cost
				heap.insert(Path{node: v.node, cost: cost})
			}
		}
	}

	w := bufio.NewWriter(os.Stdout)
	for i, cost := range minCosts {
		fmt.Fprintf(w, "%d %d\n", i, cost)
	}
	w.Flush()
}

func scanInt(sc *bufio.Scanner) int {
	sc.Scan()
	v, _ := strconv.Atoi(sc.Text())
	return v
}

// --- From ALDS1_9_C: Priority Queue

type Heap struct {
	size   int
	heap   []Path
	isHigh func(a, b Path) bool
}

func NewHeap(isHigh func(a, b Path) bool) Heap {
	heap := make([]Path, 1) // 先頭は不使用
	return Heap{size: 0, heap: heap, isHigh: isHigh}
}

func (h *Heap) insert(v Path) {
	h.size += 1
	if h.size > len(h.heap)-1 {
		h.heap = append(h.heap, v)
	} else {
		h.heap[h.size] = v
	}

	for i := h.size; i > 1; {
		parent := i / 2
		if h.isHigh(h.heap[parent], h.heap[i]) {
			break
		}
		h.heap[i], h.heap[parent] = h.heap[parent], h.heap[i]
		i = parent
	}
}

func (h *Heap) extractMax() Path {
	if h.size <= 0 {
		panic("cannot extract from empty heap")
	}

	max := h.heap[1]
	h.heap[1] = h.heap[h.size]
	h.size -= 1
	h.maxHeapify(1)

	return max
}

func (h *Heap) maxHeapify(idx int) {
	left := idx * 2
	right := left + 1
	largest := idx

	if left <= h.size {
		if h.isHigh(h.heap[left], h.heap[idx]) {
			largest = left
		}
		if right <= h.size && h.isHigh(h.heap[right], h.heap[largest]) {
			largest = right
		}
	}

	if largest != idx {
		h.heap[idx], h.heap[largest] = h.heap[largest], h.heap[idx]
		h.maxHeapify(largest)
	}
}

C++: #include <iostream>
#include <fstream>
#include <stdio.h>
#include <algorithm>
#include <queue>

using namespace std;

static const int MAX = 1000000;
static const int INFTY = (1 << 21);

int n;
vector<pair<int, int> > M[MAX];

void dijkstr(){
    int d[MAX];
    priority_queue<pair<int, int>,vector<pair<int, int> >, greater<pair<int, int> > > pq;
    fill(d, d+n, INFTY);
    
    pq.push(make_pair(0, 0));
    
    while(!pq.empty()){
        pair<int, int> f = pq.top(); pq.pop();
        int u = f.second;
        if(d[u] != INFTY) continue;
        d[u] = f.first;
        for(int i=0; i<M[u].size(); i++){
            pq.push(make_pair(f.first+M[u][i].first, M[u][i].second));
        }
    }
    
    for(int i=0; i<n; i++)
        cout << i << " " << d[i] << endl;
    
}


int main(int argc, const char * argv[]) {
    // input from txt
    /////////
    //write//
    /////////
    
    cin >> n;
    int u, k ,v, c;
    
    for(int i=0; i<n; i++){
        cin >> u >> k;
        for(int j=0; j<k; j++){
            cin >> v >> c;
            M[u].push_back(make_pair(c, v));
        }
    }
    
    dijkstr();
    
    return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;

#define MAX 10000
#define INF (1<<29)

struct Edge{
  int c, to;
};

struct state{
  int node, c;
  bool operator <(const state &b)const{
    return c > b.c;
  }
};

int n;
int d[MAX+1];
vector<Edge> G[MAX+1];
priority_queue<state> q;

void dijkstra(){

  fill(d,d+MAX+1,INF);
  q.push((state){0,0});
  d[0] = 0;

  while(!q.empty()){

    state info;
    info = q.top();
    q.pop();

    for(int i = 0; i < G[info.node].size(); i++){
      if(d[G[info.node][i].to] > G[info.node][i].c + d[info.node]){
        d[G[info.node][i].to] = G[info.node][i].c + d[info.node];
        q.push((state){G[info.node][i].to,d[info.node]});
      }
    }
  }

  for(int i = 0; i < n; i++){
    cout << i << " " << d[i] << endl;
  }



}

int main(){

  cin >> n;
  for(int i = 0; i < n; i++){
    int k, v, cc, u;
    cin >> u >> k;
    for(int j = 0; j < k; j++){
      cin >> v >> cc;
      G[u].push_back((Edge){cc,v});
    }
  }

  dijkstra();

}

C++: #include<iostream>
#include<cstdio>
#include<string>
#include<algorithm>
#include<vector>

#define INF 2000000001
#define MAX 10001
#define NIL -1

using namespace std;

typedef struct {
    int toid;
    int far;
} PATH;

vector<PATH> D[MAX];
int N;
int Dist[MAX];

void dijkstra(){//0??????????????¢??????????????£?????????
    
    bool complete[MAX];
    vector<int> S;
    
    for (int i = 0; i < N; i++) {
        complete[i] = false;
        Dist[i] = INF;
    }
 
    //???????¨????
    Dist[0] = 0;
    S.push_back(0);
    int u=0,minf;
    complete[u] = true;
    
    while (1) {
        if (S.size() == N) break;
        
        //????????????
        for (int j = 0; j < D[u].size(); j++) {
            if (!complete[D[u][j].toid] && Dist[u] + D[u][j].far < Dist[D[u][j].toid]) {
                Dist[D[u][j].toid] = Dist[u] + D[u][j].far;
            }
        }
        
        
        
        u = NIL;
        minf = INF;
        
        //?¨??????´??°
//        for (int i = 0; i < S.size(); i++) {
//            
//            for (int j = 0; j < D[S[i]].size(); j++) {
//                if (Dist[D[S[i]][j].toid] < minf && !complete[D[S[i]][j].toid]) {
//                    minf = Dist[D[S[i]][j].toid];
//                    u = D[S[i]][j].toid;
//                }
//            }
//            
//        }
        
        for (int i = 0; i < N; i++) {
            if (!complete[i] && Dist[i] < minf) {
                minf = Dist[i];
                u = i;
            }
        }
        
        S.push_back(u);
        complete[u] = true;
        //u = S.size()-1;//????????§u????????§??¨????????????????????????
    }
}

int main(){
    cin >> N;
    for (int i = 0; i < N; i++) {
        int bb1,bb2;
        cin >> bb1 >> bb2;
        for (int j = 0; j < bb2; j++) {
            PATH bb3;
            cin >> bb3.toid >> bb3.far;
            D[i].push_back(bb3);
        }
    }
    
    dijkstra();
    
    for (int i = 0; i < N; i++) {
        printf("%d %d\n",i,Dist[i]);
    }
    
    return 0;
}