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()

	list := make([][]int, n)
	weight := make([]int, n)
	for i := range list {
		list[i] = make([]int, n)
		weight[i] = NIL
		for j := range list[i] {
			list[i][j] = NIL
		}
	}

	for i := 0; i < n; i++ {
		u := scanInt()
		k := scanInt()
		for j := 0; j < k; j++ {
			v := scanInt()
			w := scanInt()
			list[u][v] = w
		}
	}

	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 i, w := range list[node.id] {
			if w == NIL {
				continue
			}
			heap.Push(h, Node{id: i, weight: w + node.weight})
		}
	}

	w := bufio.NewWriter(os.Stdout)
	for i := 0; i < n; i++ {
		fmt.Fprint(w, i)
		fmt.Fprint(w, " ")
		fmt.Fprint(w, weight[i])
		fmt.Fprintln(w)
	}
	w.Flush()
}

C++: #include<iostream>
#include<unordered_set>
#define N 105
#define UNDEFINED -1
static const int INF = (1<<21);

int n;
int u, k, v, c;
int G[N][N];
int distance[N], hasVisited[N];


void dijkstra(int s) {
    int minv;
    distance[s] = 0;
    while(true) {
        minv = INF;
        int u = UNDEFINED;
        for (int i = 0; i < n; ++i) {
            if(minv > distance[i] && hasVisited[i] != 1) {
                u = i;
                minv = distance[i];
            }
        }
        if(u == UNDEFINED) break;
        hasVisited[u] = 1;
        for (int v = 0; v < n; ++v) {
            if(distance[v] > distance[u] + G[u][v]) {
                distance[v] = distance[u] + G[u][v];
            }
        }
    }
    for (int i = 0; i < n; ++i) {
        printf("%i %i\n", i, distance[i]);
    }
}

int main() {
    for (int i = 0; i < N; ++i) {
        for (int j = 0; j < N; ++j) {
            G[i][j] = INF;
        }
        distance[i] = INF;
        hasVisited[i] = 0;
    }

    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;
                G[u][v] = c;
            }
        }

    dijkstra(0);

    return 0;
}

C++: #include <iostream>
#include <vector>

using namespace std;

int n;
vector<int> g[100];
vector<int> w[100];
int d[100];
char color[100];

void dijkstra() {
    d[0] = 0;
    color[0] = 'b';

    for (int k = 1; k < n; ++k) {
        int next;
        int mine = INT_MAX;
        for (int i = 0; i < n; ++i) {
            if (color[i] == 'b') {
                for (int j = 0; j < g[i].size(); ++j) {
                    if (d[i] + w[i].at(j) <= d[g[i].at(j)] && color[g[i].at(j)] == 'w') {
                        d[g[i].at(j)] = d[i] + w[i].at(j);
                        if (d[g[i].at(j)] <= mine) {
                            next = g[i].at(j);
                            mine = d[next];
                        }
                    }
                }
            }
        }
        color[next] = 'b';
        d[next] = mine;
    }
}

int main() {
    cin >> n;
    for (int i = 0; i < n; ++i) {
        int u;
        int k;
        cin >> u >> k;
        int v, c;
        for (int j = 0; j < k; ++j) {
            cin >> v >> c;
            g[u].push_back(v);
            w[u].push_back(c);
        }
    }
    for (int m = 0; m < n; ++m) {
        color[m] = 'w';
        d[m] = INT_MAX;
    }

    dijkstra();

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

    return 0;
}

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

const int INF = 0xfffffff;
const int MAX = 10000;

struct Edge {
	bool operator < (const Edge& e)const {
		return c > e.c;
	}
	int v;
	int c;
};

int main() {
	int n;
	vector<Edge> graph[MAX];
	priority_queue<Edge> q;
	int table[MAX];
	bool check[MAX];

	cin >> n;
	for (int i = 0; i < n; i++) {
		table[i] = INF;
		check[i] = false;
	}

	for (int i = 0; i < n; i++) {
		int u, k;
		cin >> u >> k;
		for (int j = 0; j < k; j++) {
			Edge e;
			cin >> e.v >> e.c;
			graph[u].push_back(e);
		}
	}

	int u = 0;
	table[0] = 0;
	while (true) {
		check[u] = true;

		for (int i = 0; i < graph[u].size(); i++) {
			int v = graph[u][i].v;
			int c = graph[u][i].c;
			if (table[v] > c + table[u]) {
				table[v] = c + table[u];
				Edge e;
				e.v = v;
				e.c = table[v];
				q.push(e);
			}
		}
		if (check[q.top().v])break;
		u = q.top().v; q.pop();
	}

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

	return 0;
}

C++: #include <iostream>
#pragma warning(disable:4996)
using namespace std;
const int maxn = 100 + 10;
const int maxv = 10000 + 10;
const int INF = 1 << 21;
int n;
int E;
typedef struct{
	int from, to, cost;
}Edge;

Edge e[maxv];
int d[maxn];
void bellman_ford(int s){
	fill(d, d + n, INF);
	d[s] = 0;
	while (true)	{
		bool bUpdate = false;
		for (int i = 0; i<E; i++)	{
			Edge es = e[i];
			if (d[es.from] != INF&&d[es.to]>d[es.from] + es.cost)		{
				d[es.to] = d[es.from] + es.cost;
				bUpdate = true;
			}
		}
		if (!bUpdate) break;
	}
	for (int i = 0; i<n; i++) printf("%d %d\n", i, d[i]);
}

int main(){
	scanf("%d", &n);
	int id, c;
	E = 0;
	for (int i = 0; i<n; i++){
		scanf("%d%d", &id, &c);
		while (c--){
			scanf("%d%d", &e[E].to, &e[E].cost);
			e[E].from = id;
			E++;
		}
	}
	bellman_ford(0);
	return 0;
}