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 <stdio.h>
#define INF (1<<21)

int main(void)
{
 int i,j,n,m,u,k,l,v,c,a[10000],b[10000],d[10000][10000];

 scanf("%d",&n);
 
 for(i=0;i<n;i++){
 	scanf("%d %d",&u,&k);
 	a[i]=INF;
 	b[i]=0;
 	for(j=0;j<k;j++){
 		scanf("%d %d",&v,&c);
 		d[u][v]=c;
 	}
 }
 a[0]=0;
 
 while(1){
 	
 	l=-1;
 	m=INF;
 	
 	for(i=0;i<n;i++){
 		if(a[i]<m && b[i]==0){
 			m=a[i];
 			l=i;
 		}
 	}
 	
 	if(l==-1) break;
 	
 	b[l]=1;
 	
 	for(i=0;i<n;i++){
 		if(a[i]>=d[l][i]+a[l]) a[i]=d[l][i]+a[l];
 	}
 }
 
 for(i=0;i<n;i++){
 	if(a[i]==INF) printf("%d -1\n",i);
 	else printf("%d %d\n",i,a[i]);
 }
 
 return 0;
}

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

#define INF 1<<29
#define MAXV 100

int V;      //????????°
int cost[MAXV+10][MAXV+10];

vector<int> dijkstra(int s){
    vector<int> d(V,INF);
    bool used[MAXV+10];
    for(int i=0;i<MAXV+10;i++) used[i]=false;

    d[s]=0;
    while(true){
        //??????????????????????????????????????§s??????????????¢???????°?????????????v??¨??????
        int v=-1;
        for(int u=0;u<V;u++){
            if(!used[u] and (v==-1 or d[u]<d[v])) v=u;
        }

        if(v==-1) break;
        
        used[v]=true;
        for(int u=0;u<V;u++){
            d[u] = min(d[u],d[v]+cost[v][u]);
        }
    }
    return d;
}

int main(){
    // initialize
    for(int i=0;i<MAXV+10;i++) for(int j=0;j<MAXV+10;j++) cost[i][j]=INF;

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

    vector<int> dis = dijkstra(0);
    for(int i=0;i<dis.size();i++){
        printf("%d %d\n",i,dis[i]);
    }
}

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

#define MAX 100
static const int INFTY =(1<<21);

int n,M[MAX][MAX];
int unvisited=0,decide=1,comp_decide=2;

void dijkstra(){
	int d[MAX];
	int state[MAX];
	for(int i=0;i<n;i++){
		d[i]=INFTY;
		state[i]=unvisited;
	}
	d[0]=0;
	state[0]=0;
	while(1){
		int mincost=INFTY,u=-1;
		for(int i=0;i<n;i++){
			if(d[i]<mincost&&state[i]!=comp_decide){
				u=i;
				mincost=d[i];
			}
		}
		if(u==-1) break;
		state[u]=comp_decide;
		for(int v=0;v<n;v++){
			if(state[v]!=comp_decide&&M[u][v]!=INFTY){
				if(d[v]>d[u]+M[u][v]){
					d[v]=d[u]+M[u][v];
					state[v]=decide;
				}
			}
		}
	}
	for(int i=0;i<n;i++){
			printf("%d %d\n",i,(d[i]==INFTY ? -1:d[i]));
	}
}

int main(){
	scanf("%d",&n);
	for(int i=0;i<n;i++){
		for(int j=0;j<n;j++){
			M[i][j]=INFTY;
		}
	}
	int u,k,v,c;
	for(int i=0;i<n;i++){
		scanf("%d %d",&u,&k);
		for(int j=0;j<k;j++){
			scanf("%d %d",&v,&c);
			M[u][v]=c;
		}
	}
	dijkstra();
}

C++: #include<iostream>
#define INF 1<<30
using namespace std;
int main() {
  int n; cin >> n;
  int graph[100][100];
  for (int i = 0; i < n; ++i)
    for (int j = 0; j < n; ++j) graph[i][j] = INF;
  for (int i = 0; i < n; ++i) {
    int u, k, v; cin >> u >> k;
    for (int j = 0; j < k; ++j) {
      cin >> v;
      cin >> graph[u][v];
    }
  }
  int mincost[100], flag[100] = {};
  mincost[0] = 0;
  for (int i = 1; i < n; ++i) mincost[i] = INF;
  while (1) {
    int x = -1;
    for (int i = 0; i < n; ++i)
      if (!flag[i] && (x == -1 || mincost[x] > mincost[i])) x = i;
    if (x == -1) break;
    flag[x] = 1;
    for (int i = 0; i < n; ++i)
      if (mincost[i] > mincost[x]+graph[x][i]) mincost[i] = mincost[x]+graph[x][i];
  }
  for (int i = 0; i < n; ++i) cout << i << " " << mincost[i] << endl;
  return 0;
}

C++: #include <iostream>
#include <string>
#include <unordered_map>
#include <stdio.h>
#include <list>
#include <vector>
#include <algorithm>
#include <stack>
#include <climits>
#include <queue>
using namespace std;
#define rep(i, n) for(int i = 0; i < n; ++i)
typedef long long ll;

int M[100][100];

int main()
{
	int n;cin >> n;
	rep(i,n)
		rep(j,n)M[i][j]=INT_MAX;
		
	rep(i,n)
	{
		int hoge, hogege;
		cin >> hoge >> hogege;
		rep(j,hogege)
		{
			int foo,fooo;
			cin >> foo >> fooo;
			M[i][foo]=fooo;
		}
	}

	vector<int> color(n);
	rep(i,n)color[i]=0;
	vector<int> d(n);
	rep(i,n)d[i]=INT_MAX;
	vector<int> p(n);
	d[0]=0;
	p[0]=-1;

	while (1)
	{
		int u;
		int mincost = INT_MAX;
		rep(i,n)
		{
			if((color[i]!=2)&&(d[i]<mincost))
			{
				mincost=d[i];
				u=i;
			}
		}

		if(mincost==INT_MAX)break;

		color[u] = 2;

		rep(v,n)
		{
			if(color[v] != 2&&M[u][v]!=INT_MAX)
			{
				if(d[u] + M[u][v] < d[v])
				{
					d[v] = d[u] + M[u][v];
					p[v] = u;
					color[v] = 1;
				}
			}
		}
	}
	rep(i,n)
	{
		cout<<i<<" "<<d[i]<<endl;
	}


	

	return 0;
}

C++: #include <algorithm>
#include <iostream>
#include <vector>
using namespace std;
const long long INF = 1LL << 60;    // 1.15x10^18
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }

using edge = pair<int, long long>;
using Graph = vector<vector<edge>>;

vector<long long> dijkstra(const Graph &g, int s) {
    int n = g.size();
    vector<long long> dist(n, INF);
    vector<bool> fixed(n);
    dist[s] = 0;
    while (true) {
        int u = -1;
        for (int i = 0; i < n; i++) if (!fixed[i]) {
            if (u == -1 || dist[i] < dist[u]) u = i;
        }
        if (u == -1) break;
        fixed[u] = true;
        for (auto &e: g[u]) chmin(dist[e.first], dist[u] + e.second);
    }
    return dist;
}

int main() {
    int V; cin >> V;
    Graph g(V);
    for (int i = 0; i < V; i++) {
        int u, k; cin >> u >> k;
        while (k--) {
            int v, c; cin >> v >> c;
            g[u].emplace_back(v, c);
        }
    }
    auto dist = dijkstra(g, 0);
    for (int u = 0; u < V; u++) cout << u << " " << dist[u] << endl;
    return 0;
}