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<iostream>
#include<vector>

struct Edge {
	int to, weight;
};

int main()
{
	int n, u, k, v, c, distance[100]{}, upd_num = 1;
	bool must_update[100]{ 1 };
	std::vector<Edge> dest[100];

	std::cin >> n;
	for (int i = 0; i < n; ++i)
	{
		std::cin >> u >> k;
		for (int j = 0; j < k; ++j)
		{
			std::cin >> v >> c;
			dest[u].push_back({ v, c });
		}
		if (i)
			distance[i] = 2000000000;
	}

	while (upd_num)
		for (int i = 0; i < n && upd_num; i++)
		{
			if (!must_update[i]) continue;

			must_update[i] = false;
			upd_num--;
			for (auto e : dest[i])
			{
				int tmp = distance[i] + e.weight;
				if (tmp < distance[e.to])
				{
					distance[e.to] = tmp;
					if (!must_update[e.to])
					{
						must_update[e.to] = true;
						upd_num++;
					}
				}
			}
		}

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

	return 0;
}

C++: #include<iostream>
#include<vector>
#include<algorithm>
#define MAX_V 100
#define INF 1e9
using namespace std;
int cost[MAX_V][MAX_V];
int d[MAX_V];
bool used[MAX_V];
int V;
void dijkstra(int s) {
	for (int i = 0; i < V; i++) {
		d[i] = INF;
		used[i] = false;
	}
	d[s] = 0;
	while (true) {
		int v = -1;
		for (int u = 0; u < V; u++) {
			if (!used[u] && ((v == -1) || d[u] < d[v])) {
				v = u;
			}
		}
		//全ての頂点が到達済み
		if (v == -1) {
			break;
		}
		//集合に新たに頂点を追加
		used[v] = true;
		for (int u = 0; u < V; u++) {
			d[u] = min(d[u], d[v] + cost[v][u]);
		}
	}
}

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

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

C++: #include <cstdio>
static const int INFTY = (1 << 21);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n, **M;
int *d;

void dijkstra() {
    int u, minv;
    int d[n], color[n];

    for (int i = 0; i < n; i++) {
        d[i] = INFTY;
        color[n] = WHITE;
    }
    d[0] = 0;

    while (1) {
        u = -1;
        minv = INFTY;
        for (int i = 0; i < n; i++) {
            if (color[i] != BLACK && d[i] < minv) {
                u = i;
                minv = d[i];
            }
        }

        if (u == -1) { break; }

        color[u] = BLACK;
        for (int v = 0; v < n; v++) {
            if (color[v] != BLACK && M[u][v] != INFTY) {
                if (d[u] + M[u][v] < d[v]) {
                    d[v] = d[u] + M[u][v];
                    color[v] = GRAY;
                }             
            }
        }
    }
    
    for (int i = 0; i < n; i++) {
        printf("%d %d\n", i, d[i]);
    }
}

int main() {
    scanf("%d", &n);

    M = new int*[n];
    for (int i = 0; i < n; i++) {
        M[i] = new int[n];
        for (int j = 0; j < n; j++) {
            M[i][j] = INFTY;
        }
    }

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

    dijkstra();

    return 0;
}

C++: #include<iostream>
using namespace std;
static const int N = 100;
static const int INF = 10000000;
static const int WHITE =0;
static const int GRAY =1;
static const int BLACK =2;

int n,A[N][N]; //隣接行列

void dijkstra(){
    int min ;
    int d[N],color[N];

    for(int i =0;i<n;i++){
        d[i] = INF;
        color[i] =WHITE;
    }
    d[0] =0;
    color[0] = GRAY;
    while(1){
        min = INF;
        int u = -1;
        for(int i =0;i <n;i++){
            if(min > d[i] && color[i] != BLACK){
                u = i;
                min  = d[i];
            }
        }
        if(u ==-1) break;
        color[u] = BLACK;
        for(int v =0;v<n;v++){
            if(color[v] != BLACK && A[u][v] != INF){
                if(d[v] > d[u] + A[u][v]){
                    d[v] = d[u] + A[u][v];
                    color[v] =GRAY; 
                }
            }
        }
    }

    for(int i = 0;i<n;i++){
        cout<< i << " "<< (d[i] == INF ? -1 :d[i]) << endl; 
    }
}

int main(){
    cin >> n;
    for(int i=0;i<n;i++){
        for(int j =0;j<n;j++){
            A[i][j] = INF;
        }
    }
    
    int k,c,u,v;
    for(int i =0;i<n;i++){
        cin >> u >> k;
        for(int j =0;j<k;j++){
            cin >> v >> c;
            A[u][v] = c;
        }
    }

    dijkstra();

    return 0;
}

C++: #include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <limits.h>


#define MAX_E 20
#define MAX_V 7
#define INF 100000

typedef struct edge{
    int from;
    int to;
    int cost;
}edge;


edge es[MAX_E];

int distance[MAX_V];

void bellman_ford(int n, int s, int e) {
    int i, update;
    
    for (int i = 0; i < MAX_V; i++) distance[i] = INF;
    distance[s] = 0;
    while (1) {
        update = 0;
        for (i = 0; i < e; i++) {
            edge e = es[i];
            if (distance[e.from] != INF && distance[e.to] > distance[e.from] + e.cost) {
                distance[e.to] = distance[e.from] + e.cost;
                update = 1;
            }
        }
        if (!update) break;
    }
}


int main( ){
    
    int n, i, j, l, u, v, k, c;
    scanf("%d", &n);
    
    
    l = 0;
    for (i = 0; i < n; i++) {
        scanf("%d %d", &u, &k);
        
        for (j =0 ; j < k; j++) {
            scanf("%d %d", &v, &c);
            es[l].from = u;
            es[l].to = v;
            es[l].cost = c;
            l++;
        }
    }
    
    bellman_ford(n, 0, l);
    
    for (i=0; i<n; i++) {
        printf("%d %d\n", i, distance[i]);
    }
    
    return 0;
}