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 <iostream>
#include <queue>
#include <utility>
#include <vector>

#define MAX_NODE 10000
#define INF 1000000000

using namespace std;

struct Edge {
	int to, w;
};

typedef pair<int, int> P;

vector<Edge> adj[MAX_NODE];
int d[MAX_NODE];

void dijkstra(int n, int start) {
	priority_queue<P, vector<P>, greater<P> > heap;
	fill(d, d + n, INF);
	d[start] = 0;
	heap.push({0, start});

	while (!heap.empty()) {
 		P p = heap.top();
 		heap.pop();
 		int from = p.second;
 		if (d[from] < p.first)
 			continue;
 		for (int i = 0; i < adj[from].size(); i++) {
 			Edge e = adj[from][i];
	 		if (d[from] + e.w < d[e.to]) {
	 			d[e.to] = d[from] + e.w;
	 			heap.push( {d[e.to], e.to} );
	 		}
	 	}
	}
}

int main(){
	int n,u,k,c,v;
	cin>>n;
	for(int i=0;i<n;i++){
		cin>>u>>k;
		for(int j=0;j<k;j++){
			cin>>v>>c;
			adj[u].push_back({v,c});
		}
	}
	dijkstra(n,0);
	for(int i=0;i<n;i++){
		cout<<i<<" "<<d[i]<<"\n";
	}
	return 0;
}

C++: #include <iostream>
#include <vector>
using namespace std;
int n;
/*
int dat[100][100];
int cost[100];
int done[100];

void prim(){
	for(int i=0;i<n;i++){
		cost[i]=1<<21;
		done[i]=0;
	}
	int s=0;	
	int next, ncost=1<<21;
	done[s]=1;
	cost[s]=0;
	while(1){
		ncost=1<<21;
		for(int j=0;j<n;j++){
			if(done[j]){
				for(int i=0;i<n;i++){
					if(dat[j][i]!=-1){
						if(cost[i]>=dat[j][i]&&!done[i]){
							cost[i]=dat[j][i];
						}
						if(ncost>cost[i]&&!done[i]){
							next=i;
							ncost=cost[i];
						}
					}
				}
			}
		}
//		cout<<"next:"<<next<<" cost:"<<cost[next]<<endl;
		done[next]=1;
		int flag=true;
		for(int i=0;i<n;i++){
			if(!done[i]) flag = false;
		}
		if(flag)
			return;
	}
}


void dijk(){
	for(int i=0;i<n;i++){
		cost[i]=1<<21;
		done[i]=0;
	}
	int s=0;	
	int next, ncost=1<<21;
	done[s]=1;
	cost[s]=0;
	while(1){
		ncost=1<<21;
		for(int j=0;j<n;j++){
			if(done[j]){
				for(int i=0;i<n;i++){
					if(dat[j][i]!=0){
						if(cost[i]>=dat[j][i]+cost[j]){
							cost[i]=dat[j][i]+cost[j];
						}
						if(ncost>cost[i]&&!done[i]){
							next=i;
							ncost=cost[i];
						}
					}
				}
			}
		}
//		cout<<"next:"<<next<<" cost:"<<cost[next]<<endl;
		done[next]=1;
		int flag=true;
		for(int i=0;i<n;i++){
			if(!done[i]) flag = false;
		}
		if(flag)
			return;
	}
}
*/

vector<vector<int> > dat;
int cost[10000];
int done[10000];

void dijk2(){
	for(int i=0;i<n;i++){
		cost[i]=1<<21;
		done[i]=0;
	}
	int s=0;	
	int next, ncost=1<<21;
	done[s]=1;
	cost[s]=0;
	while(1){
		top:
		ncost=1<<21;
		for(int j=0;j<n;j++){
			if(done[j]){
				for(int i=0;i<n;i++){
					if(dat[j][i]!=0){
						if(!done[i]){
							if(cost[i]>=dat[j][i]+cost[j]){
								cost[i]=dat[j][i]+cost[j];
							}
							if(ncost>cost[i]){
								next=i;
								ncost=cost[i];
							}
						}
					}
				}
			}
		}
//		cout<<"next:"<<next<<" cost:"<<cost[next]<<endl;
		done[next]=1;
		for(int i=0;i<n;i++){
			if(!done[i]) goto top;
		}
		return;
	}
}



int main(){
	int num, from, dist, c;
	cin>>n;	
	dat.reserve(n);
	for(int i=0;i<n;i++){
		vector<int> d(n);
		dat.push_back(d);
	}
	for(int i=0;i<n;i++){
		cin>>from>>num;
		for(int j=0;j<num;j++){
			cin>>dist>>c;
			dat[from][dist]=c;
		}
	}
	dijk2();
	for(int i=0;i<n;i++){
		cout<<i<<" "<<cost[i]<<endl;
	}
	return 0;
}

C++: #include <bits/stdc++.h>

using namespace std;

vector<int> adja[10000], cost[10000];

#define INF (1 << 30)

int main() {
	int n, id, k;

	cin >> n;
	for (int i = 0; i < n; ++i) {
		cin >> id >> k;
		adja[id].resize(k);
		cost[id].resize(k);
		for (int j = 0; j < k; ++j) {
			cin >> adja[id][j] >> cost[id][j];
		}
	}

	priority_queue<pair<int, int>> que;
	que.push(make_pair(0, 0)); //cost, node
	int best[10000];
	fill(best, best + n, INF);
	best[0] = 0;

	while (!que.empty()) {
		pair<int, int> top = que.top();
		que.pop();

		if (best[top.second] < top.first) {
			continue;
		}

		for (int j = 0, len = adja[top.second].size(); j < len; ++j) {
			if (best[adja[top.second][j]] > top.first + cost[top.second][j]) {
				best[adja[top.second][j]] = top.first + cost[top.second][j];
				que.push(make_pair(top.first + cost[top.second][j], adja[top.second][j]));
			}
		}
	}

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

	return 0;
}

C++: 
#include<bits/stdc++.h>

using namespace std;

const int maxn=1e4+5;
const int inf=(1<<20);
const int white=0;
const int gray=1;
const int black=2;

int n;
vector<pair<int,int> >adj[maxn];

void dijkstra()
{
    priority_queue<pair<int,int> >q;
    int book[maxn],d[maxn];
    for(int i=0;i<n;i++){
        d[i]=inf;
        book[i]=0;
    }
    d[0]=0;
    q.push(make_pair(0,0));
    while(!q.empty()){
        pair<int,int>f=q.top();
        q.pop();
        int u=f.second;
        book[u]=1;
//        if(d[u]<f.first*(-1)){
//            continue;
//        }
        for(int j=0;j<adj[u].size();j++){
            int v=adj[u][j].first;
            if(book[v]==1){
                continue;
            }
            if(d[v]>d[u]+adj[u][j].second){
                d[v]=d[u]+adj[u][j].second;
                q.push(make_pair(d[v]*(-1),v));
            }
        }
    }
    for(int i=0;i<n;i++){
        cout<<i<<" "<<(d[i]==inf?-1:d[i])<<endl;
    }
}

int main()
{
    scanf("%d",&n);
    int u,k,v,c;
    for(int i=0;i<n;i++){
        cin>>u>>k;
        for(int i=0;i<k;i++){
            cin>>v>>c;
            adj[u].push_back(make_pair(v,c));
        }
    }
    dijkstra();
    return 0;
}