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 <iostream>
#include <limits>

#define FOR(i,a,b) for (int i = (a); i < (b); ++i)

constexpr int MAXN = 100;
constexpr int MAXINT = std::numeric_limits<int>::max();


int G[MAXN][MAXN];
int D[MAXN];
int C[MAXN];
int P[MAXN];
int n;

int main() {
    std::cin >> n;
    FOR(i, 0, n)
    FOR(j, 0, n)
    {
        G[i][j] = MAXINT;
    }

    FOR(i, 0, n){
        int id, e;
        std::cin >> id >> e;
        FOR(i, 0, e) {
            int v, c;
            std::cin >> v >> c;
            G[id][v] = c;
        }
    }

    FOR(i, 0, n) D[i] = MAXINT;

    int r = -1;
    D[0] = 0;
    while (true) {
        int mincost = MAXINT;
        int t;
        for (int i = 0; i < n; i++) {
            if ((C[i] == 0)  && (D[i] < mincost)) {
                mincost = D[i];
                t = i;
            }
        }

        if (mincost == MAXINT) {
            break;
        }

        C[t] = 1;
        P[t] = r;

        for (int i = 0; i < n; i++) {
            if ((C[i] == 0) && (G[t][i] != MAXINT) && ((D[t] + G[t][i]) < D[i])) {
                D[i] = D[t] + G[t][i];
            }
        }
        r = t;
    }
    FOR(i, 0, n) {
        std::cout << i << " " << D[i] << std::endl;
    }
}

C++: #include <algorithm>
#include <iostream>
#include <string>
using namespace std;
static const int NMAX = 100;
#define INF (1 << 30)
int ADJ[NMAX][NMAX];

int main() {
  int n;
  cin >> n;
  for (int i = 0; i < n; i++)
    for (int j = 0; j < n; j++)
      ADJ[i][j] = INF;

  for (int i = 0; i < n; i++) {
    int id, nn;
    cin >> id  >> nn;
    for (int j = 0; j < nn; j++) {
      int to, weight;
      cin >> to >> weight;
      ADJ[id][to] = weight;
    }
  }

  bool visited[n];
  int dist[n];

  // add node 0
  for (int i = 0; i < n; i++) {
    dist[i] = ADJ[0][i];
    visited[i] = false;
  }
  visited[0] = true;
  dist[0] = 0;

  while (true) {
    int minnode = -1;
    int mincost = INF;
    // find nearest node
    for (int i = 0; i < n; i++) {
      if (visited[i] == false && dist[i] < mincost) {
        minnode = i;
        mincost = dist[i];
      }
    }
    if (minnode == -1)
      break;

    // add node
    visited[minnode] = true;

    // update dist
    for (int i = 0; i < n; i++) {
      if (visited[i] == false)
        dist[i] = min(dist[i], dist[minnode] + ADJ[minnode][i]);
    }
  }

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

C++: a

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

static const int MAX = 100;
static const int INFTY = (1<<21);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n,M[MAX][MAX];

void dijkstra(){
    int minv;
    int d[MAX],color[MAX];
    
    for(int i=0; i<n; i++){
        d[i] = INFTY;
        color[i] = WHITE;
    }
    
    d[0] = 0;
    //color[0] = GRAY;
    while (1) {
        minv = INFTY;
        int u = -1;
        for(int i=0; i<n; i++){
            if(minv > d[i] && color[i] != BLACK){
                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[v] > d[u] + M[u][v]){
                    d[v] = d[u]+M[u][v];
                    color[v] = GRAY;
                }
            }
        }
    }
    for(int i=0; i<n; i++){
        cout << i << " " << (d[i]==INFTY ? -1 : d[i]) << endl;
    }
}

int main(){
    cin >> n;
    for(int i=0; i<n; i++){
        for(int j=0; j<n; j++){
            M[i][j] = INFTY;
        }
    }
    
    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;
            M[u][v] = c;
        }
    }
    
    dijkstra();
}

C++: #include <iostream>
#include <algorithm>
#define N 100
#define INF (1<<30)
using namespace std;

int n, M[N][N], d[N], color[N] = {0};

void Dijk(int s) {
	int min;
	for (int i = 0;i < n;i++) d[i] = INF;
	d[s] = 0;
	color[s] = 1;
	while (true) {
		int u=-1;
	    min = INF;
		for (int i = 0;i < n;i++) {
			if (color[i] != 2 && d[i] < min)
			{
				u = i;
				min = d[u];
			}
		}

		if (u==-1) break;

		color[u] = 2;

		for (int v = 0;v < n;v++) {
			if (color[v] != 2 && M[u][v] != INF)
				if (d[v] > d[u] + M[u][v]) {
					d[v] = d[u] + M[u][v];
					color[v] = 1;
				}
		}
	}

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

}

int main() {

	for (int i = 0;i < N;i++)
		for (int j = 0;j < N;j++) M[i][j] = INF;

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

	Dijk(0);

}