Go: package main

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

type Item struct {
	value    int // The value of the item; arbitrary.
	priority int // The priority of the item in the queue.
	// The index is needed by update and is maintained by the heap.Interface methods.
	index int // The index of the item in the heap.
}
type PriorityQueue []*Item

func (pq PriorityQueue) Len() int { return len(pq) }
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 = i
	pq[j].index = j
}
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
}

type Q struct {
	pq *PriorityQueue
	ds map[int]int // It has always same value as pq. For random access.
}

func newQ() *Q {
	pq := new(PriorityQueue)
	heap.Init(pq)
	return &Q{
		pq: pq,
		ds: make(map[int]int),
	}
}
func (q *Q) pop() (u, d int) {
	item := heap.Pop(q.pq).(*Item)
	delete(q.ds, item.value)
	return item.value, item.priority
}
func (q *Q) get(u int) (int, bool) { // returns d
	d, ok := q.ds[u]
	return d, ok
}
func (q *Q) set(u, d int) {
	q.ds[u] = d
	for _, item := range *q.pq {
		if item.value != u {
			continue
		}

		item.priority = d
		heap.Fix(q.pq, item.index)
		return
	}
	heap.Push(q.pq, &Item{
		priority: d,
		value:    u,
	})
}
func (q *Q) len() int {
	return len(q.ds)
}

func main() {
	r := bufio.NewReader(os.Stdin)

	var n int
	fmt.Fscan(r, &n)
	cs := make([]map[int]int, n) // []v_i -> c_i
	for h := 0; h < n; h++ {
		var u, k int
		fmt.Fscan(r, &u, &k)
		m := make(map[int]int)
		for i := 0; i < k; i++ {
			var v, c int
			fmt.Fscan(r, &v, &c)
			m[v] = c
		}

		cs[u] = m
	}

	q := newQ()
	q.set(0, 0)
	visited := make(map[int]struct{})
	out := make([]int, n)

	for q.len() > 0 {
		u, d := q.pop()
		for uu, c := range cs[u] {
			// Consider the connection between u and uu.
			if _, ok := visited[uu]; ok {
				continue
			}
			dd := d + c
			if d, ok := q.get(uu); !ok || d > dd {
				q.set(uu, dd)
			}
		}

		out[u] = d
		visited[u] = struct{}{}
	}

	for u, d := range out {
		fmt.Println(u, d)
	}
}

C++: #include <bits/stdc++.h>
#define rep(i,n) for (int i = 0; i < (n); ++i)
using namespace std;
typedef long long ll;

int n;
vector<pair<int, int> > adj[10000];
string color[10000];
int d[10000];
const int INF = 1001001001;
priority_queue<pair<int, int>, vector<pair<int, int> >, greater<pair<int, int> > > Q;

void dijkstra(int s){
    rep(i, n){
        color[i] = "WHITE";
        d[i] = INF;
    }
    d[s] = 0;

    Q.push(make_pair(0, s));

    while(!Q.empty()){
        pair<int, int> p = Q.top(); Q.pop();
        int u = p.second;
        color[u] = "BLACK";

        //if(d[u] < p.first) continue;

        for (int i = 0; i < adj[u].size(); i++){
            int v = adj[u][i].second;
            if(color[v] != "BLACK"){
                if(d[u] + adj[u][i].first < d[v]){
                    d[v] = d[u] + adj[u][i].first;
                    color[v] = "GRAY";
                    Q.push(make_pair(d[v], v));
                }
            }
        }
    }
}

int main() {
    cin >> n;
    rep(i, n){
        int u; cin >> u;
        int k; cin >> k;
        rep(j, k){
            int v, c; cin >> v >> c;
            adj[i].push_back(make_pair(c, v));
        }
    }
    dijkstra(0);
    rep(i, n){
        cout << i << " " << d[i]  << endl;
    }

    return 0;
}

C++: #include <iostream>
#include <vector>
#include <queue>
#include <algorithm>
#include <functional>
#include <utility>
using namespace std;

const int INF = 1 << 29;

struct Edge{
    int to, cost;
};
typedef pair<int, int> P;

int d[10001];

int main()
{
    int n,u,k,v,c;
    
    cin >> n;
    fill(d, d + n, INF);
    vector<Edge> G[10001];
    for(int i = 0; i < n; ++i){
        cin >> u >> k;
        for(int j = 0; j < k; ++j){
            cin >> v >> c;
            Edge e = {v, c};
            G[u].push_back(e);
        }
    }
    
    priority_queue<P, vector<P>, greater<P>> que;
    d[0] = 0;
    que.push(P(0,0));
    
    while(!que.empty()){
        P p = que.top(); que.pop();
        int v = p.second;
        if(d[v] < p.first) continue;
        for(int i = 0; i < G[v].size(); ++i){
            Edge e = G[v][i];
            if(d[e.to] > d[v] + e.cost){
                d[e.to] = d[v] + e.cost;
                que.push(P(d[e.to], e.to));
            }
        }
    }
    
    for(int i = 0; i < n; ++i){
        cout << i << ' ' << d[i] << endl;
    }
    
}

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

const long long MAX_N = 200000;
long long max_mdif, max_pdif, data, c, ans, s[MAX_N];
int main() {

	max_mdif = 0;
	max_pdif = 0;
	c = 0;
	cin >> data;

	for (int i = 0; i < data; ++i) {
		cin >> s[i];
	}

	for (int i = 1; i < data; ++i) {
		if (s[i] > s[i - 1]) {
			max_pdif += s[i] - s[i - 1];
			c++;
		}
	}
	if (c == 0) {
		for (int i = 1; i < data; ++i) {
			if (s[data - i] < s[data - i - 1]) {
				max_mdif = min(s[data - i] - s[data - i - 1], max_mdif);
			}
		}
	}
	if (c > 0) {
		ans = max_pdif;
	} else {
		ans = max_mdif;
	}

	cout << ans << endl;

	return 0;
}

C++: //
//  main.cpp
//  单元最短路径
//
//  Created by 陆昱珉 on 2018/12/26.
//  Copyright © 2018 Lu. All rights reserved.
//

//dijkstra algorithm

#include <stdio.h>
#define INF 999999

int n, k;
int color[10010], d[10010];
int map[10010][10010];

int dijkstra(int s)
{
    for(int i = 0; i < n; i ++)
    {
        d[i] = INF;
    }
    d[s] = 0;
    while(1)
    {
        int min = INF;
        int u = -1;
        for(int i = 0; i < n; i ++)
        {
            if(min > d[i] && color[i] != 1)
            {
                u = i;
                min = d[i];
            }
        }
        if(u == -1)
            break;
        color[u] = 1;//染色，以防后面重复使用
        for(int i = 0; i < n; i ++)
        {
            if(color[i] != 1 && map[u][i] != INF)
                if(d[i] > d[u] + map[u][i])
                    d[i] = d[u] + map[u][i];
        }
    }
    return 0;
}

int main(void)
{
    int x, y, v;
    scanf("%d", &n);
    for(int i = 0; i < n; i ++)
        for(int j = 0; j < n; j ++)
            map[i][j] = INF;
    for(int i = 0; i < n; i ++)
    {
        scanf("%d%d", &x, &k);
        for(int j = 0; j < k; j ++)
        {
            scanf("%d%d", &y, &v);
            map[x][y] = v;
        }
    }
    dijkstra(0);
    
    for(int i = 0; i < n; i ++)
    {
        if(d[i] != INF)
            printf("%d %d", i, d[i]);
        printf("\n");
    }
    return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
using namespace std;
static const int MAX=100;
static const int INFTY=2000000000;
static const int WHITE=0;
static const int GRAY=1;
static const int BLACK=2;
int n;
vector<pair<int,int> > adj[MAX];
void dijkstra(){
    priority_queue<pair<int,int> >PQ;
    int d[MAX],color[MAX];
    for(int i=0;i<n;i++){
        d[i]=INFTY;
        color[i]=WHITE;
    }
    d[0]=0;
    PQ.push(make_pair(0,0));
    color[0]=GRAY;
    while(!PQ.empty()){
        pair<int,int> f=PQ.top();PQ.pop();
        int u=f.second;
        color[u]=BLACK;
        if(d[u]<f.first*(-1))continue;
        for(int j=0;j<adj[u].size();j++){
            int v=adj[u][j].first;
            if(color[v]==BLACK)continue;
            if(d[v]>d[u]+adj[u][j].second){
                d[v]=d[u]+adj[u][j].second;
                PQ.push(make_pair(d[v]*(-1),v));
                color[v]=GRAY;
            }
        }
    }
    for(int i=0;i<n;i++)
        cout<<i<<" "<<(d[i]==INFTY?-1:d[i])<<"\n";
}
int main(){
    int k,u,v,c;
    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(make_pair(v,c));
        }
    }
    dijkstra();
    return 0;
}