Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

// I/O
type Scanner struct {
	sc *bufio.Scanner
}

func NewScanner() *Scanner {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Buffer(make([]byte, 1024), int(1e+9))
	return &Scanner{sc}
}

func (s *Scanner) nextStr() string {
	s.sc.Scan()
	return s.sc.Text()
}

func (s *Scanner) nextInt() int {
	i, e := strconv.Atoi(s.nextStr())
	if e != nil {
		panic(e)
	}
	return i
}

func (s *Scanner) nextFloat() float64 {
	f, e := strconv.ParseFloat(s.nextStr(), 64)
	if e != nil {
		panic(e)
	}
	return f
}

func (s *Scanner) nextRuneSlice() []rune {
	return []rune(s.nextStr())
}

func (s *Scanner) nextIntSlice(n int) []int {
	res := make([]int, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextInt()
	}
	return res
}

func (s *Scanner) nextFloatSlice(n int) []float64 {
	res := make([]float64, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextFloat()
	}
	return res
}

// Arithmetic
func max(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m < i {
			m = i
		}
	}
	return m
}

func min(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m > i {
			m = i
		}
	}
	return m
}

func abs(x int) int {
	if x > 0 {
		return x
	}
	return -x
}

func pow(x, y int) int {
	res := 1
	for i := 0; i < y; i++ {
		res *= x
	}
	return res
}

func ceil(a, b int) int {
	if a%b == 0 {
		return a / b
	} else {
		return a/b + 1
	}
}

// Sort
type RuneSlice []rune

func (a RuneSlice) Len() int           { return len(a) }
func (a RuneSlice) Less(i, j int) bool { return a[i] < a[j] }
func (a RuneSlice) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }

// Main
type Node struct {
	cost int
	done bool
}

type Edge struct {
	to, cost int
}

const INF = 1 << 60

func main() {
	sc := NewScanner()
	wtr := bufio.NewWriter(os.Stdout)
	N := sc.nextInt()
	nodes := make([]Node, N)
	for i := 0; i < N; i++ {
		nodes[i].cost = INF
	}
	E := make([][]Edge, N)
	for i := 0; i < N; i++ {
		id, k := sc.nextInt(), sc.nextInt()
		for j := 0; j < k; j++ {
			to, cost := sc.nextInt(), sc.nextInt()
			E[id] = append(E[id], Edge{to, cost})
		}
	}
	nodes[0].cost = 0
	for {
		cur := 0
		minCost := INF
		for i := 0; i < N; i++ {
			n := nodes[i]
			if !n.done && n.cost < minCost {
				cur = i
				minCost = n.cost
			}
		}
		if minCost == INF {
			break
		}
		nodes[cur].done = true
		for i := 0; i < len(E[cur]); i++ {
			to, cost := E[cur][i].to, E[cur][i].cost+nodes[cur].cost
			if !nodes[to].done && cost < nodes[to].cost {
				nodes[to].cost = cost
			}
		}
	}

	for i := 0; i < N; i++ {
		fmt.Fprintln(wtr, i, nodes[i].cost)
	}
	wtr.Flush()
}

C++: #include <cstdio>
#include <unordered_map>
#define N 100
#define INF 0x7FFFFFFF

void solve(std::unordered_map<int, int> a[N], const int n){
    std::unordered_map<int, int> result;
    result.insert(std::make_pair(0, 0));
    while(result.size() != n){
        std::pair<int, int> newV;
        newV.first = INF;
        newV.second = INF;
        for(auto &x: result){
            for(auto &y: a[x.first]){
                int w = y.second + x.second;
                if(result.find(y.first) == result.end() && newV.second > w){
                    newV.first = y.first;
                    newV.second = w;
                }
            }
        }
        result.insert(newV);
    }
    for(int i = 0; i < n; ++i){
        std::printf("%d %d\n", i, result.find(i)->second);
    }
}

int main(){
    int n;
    std::scanf("%d", &n);
    std::unordered_map<int, int> a[N];
    for(int i = 0; i < n; ++i){
        int id;
        std::scanf("%d", &id);
        int num;
        std::scanf("%d", &num);
        for(int j = 0; j < num; ++j){
            std::pair<int, int> v;
            std::scanf("%d", &v.first);
            std::scanf("%d", &v.second);
            a[i].insert(v);
        }
    }
    solve(a, n);
    return 0;
}

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

typedef pair<int, int> P;
const int N = 2e5;
const int INF = 1e9;

struct edge{ int to,cost; };
vector< edge > G[N];
int n;

void dikstra(int s){
  priority_queue<P,vector<P>,greater<P>> que;
  int d[N]; //sからの最短距離
  fill(d,d+N,INF);
  d[s] = 0;
  que.push({0,s}); //{頂点,最短距離}

  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( {d[e.to],e.to} );
      }
    }
  }

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

signed main(){
  cin.tie(0);
  ios::sync_with_stdio(false);

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

  return 0;
}

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

constexpr int INF = 1 << 30;

void read_graph(int n, vector<vector<pair<int, int>>> & Es){
    int u, k, v, c;
    while (n--){
        cin >> u >> k;
        while(k--){
            cin >> v >> c;
            Es[u].push_back(pair<int, int>(v, c));
        }
    }
}

void dijkstra(int start, const vector<vector<pair<int, int>>> & Es, vector<int> & dist){
    priority_queue<pair<int, int>, vector< pair<int, int> >, greater<pair<int, int> > > pq;
    pq.emplace(0, start);
    int d, u, v, c;
    while(!pq.empty()){
        tie(d, u) = pq.top();
        pq.pop();
        if (dist[u] < d) continue;
        dist[u] = d;
        for (auto p : Es[u]){
            tie(v, c) = p;
            if (d + c < dist[v]){
                dist[v] = d + c;
                pq.emplace(d + c, v);
            }
        }
    }
}

int main()
{
    ios::sync_with_stdio(false);
    int n = 0;
    cin >> n;
    vector< vector< pair<int, int> > > Es(n);
    vector<int> dist(n, INF);
    
    read_graph(n, Es);
    dijkstra(0, Es, dist);
    
    for (int i = 0; i != n; ++i){
        cout << i << ' ' << dist[i] << endl;
    }
    return 0;
}

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();
	
	return 0;
}