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 <bits/stdc++.h>
using namespace std;
 
#define INF (1 << 30)
 
struct edge{
 
  int cost, to;
 
};
 
struct state{
 
  int node, cost;
  bool operator <(const state &b)const{
    return cost > b.cost;
  }
};
 
int n;
int d[10001];
vector<edge> glaph[10001];
priority_queue<state> qu;
 
void sss(){
 
  fill(d,d+10001,INF);
  qu.push((state){0,0});
  d[0] = 0;
 
  while(!qu.empty()){
 
    state info;
    info = qu.top();
    qu.pop();
 
    for(int i = 0; i < (double)glaph[info.node].size(); i++){
      if(d[glaph[info.node][i].to] > glaph[info.node][i].cost + d[info.node]){
      d[glaph[info.node][i].to] = glaph[info.node][i].cost + d[info.node];
      qu.push((state){glaph[info.node][i].to,d[info.node]}); 
      }
    }
  }
 
  for(int i = 0; i < n; i++){
    cout << i << " " << d[i] << endl;
  }
   
 
 
 
}
 
int main(){
 
  cin >> n;
 
  for(int i = 0; i < n; i++){
    int k, v, c, u;
    cin >> u >> k;
    for(int j = 0; j < k; j++){
      cin >> v >> c;
      glaph[u].push_back((edge){c,v});
    }
  }
 
  sss();
 
 
}

C++: #include <iostream>
#include <vector>
#include <utility>
#include <string>
#include <cmath>
#include <algorithm>
#include <string>
#include <iomanip>
#include <cstdio>
#include <queue>

using namespace std;
using ll = long long;
using ull = unsigned long long;

constexpr ll LL_MAX = numeric_limits<ll>::max();
constexpr ull ULL_MAX = numeric_limits<ull>::max();
constexpr ll I_MAX = numeric_limits<int>::max();
constexpr ull UI_MAX = numeric_limits<unsigned int>::max();

#define rep(i,a,b) for(int i=a;i<b;i++)
#define rrep(i,a,b) for(int i=a-1;i>=b;i--)

auto sumdig(ll num) {
	ll dig, sum;
	sum = 0;
	while (num) {
		dig = num % 10;
		sum = sum + dig;
		num = num / 10;
	}
	return sum;
}



struct edge {
	int from;
	int to;
	int cost=1;
};


auto dijkstra(vector<vector<edge>> &g, int start = 0) {
	vector<int> d(g.size(), I_MAX);
	vector<bool> flag(g.size(), false);
	d[start] = 0;
	priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int,int>>> nodes;//first dist, second edgenum
	nodes.push(pair<int, int>(0, start));


	while (!nodes.empty()) {
		pair<int, int> n = nodes.top();
		int s_node = n.second;
		nodes.pop();
		if (n.first > d[n.second])continue;
		rep(i, 0, g[s_node].size()) {
			int new_dist = d[s_node] + g[s_node][i].cost;
			int n_num = g[s_node][i].to;
			if (new_dist < d[n_num]) {
				nodes.push(make_pair(new_dist, n_num));
				d[n_num] = new_dist;
			}
		}
	}
	return d;
}

int main() {
	int n;
	cin >> n;
	vector<edge> empty;
	vector<vector<edge>> g(n, empty);
	vector<int> ans;
	
	rep(i, 0, n) {
		int temp;
		cin >> temp;//頂点番号はいらん
		cin >> temp;

		rep(j, 0, temp) {
			int tc, tt;
			cin >> tt >> tc;
			edge tn = { i,tt,tc };
			g[i].push_back(tn);
		}
	}

	ans = dijkstra(g, 0);
	
	rep(i, 0, ans.size()) {
		cout << i << " " << ans[i] << endl;
	}

	return 0;
}

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

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

int n, M[MAX][MAX];
int d[MAX];
int color[MAX];

void dijkstra(){
  int minv;

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

  d[0] = 0;
  color[0] = 1;
  while(1){
    minv = INFTY;
    int u = -1;
    for(int i = 0; i < n; i++){
      if(minv > d[i] && color[i] != 2){
        u = i;
        minv = d[i];
      }
    }

    if(u == -1){
      break;
    }
    color[u] = 2;

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

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

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

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

  return 0;
}

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

#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)   FOR(i,0,n)
#define MOD 1000000007

typedef long long int ll;

//const ll INF=(ll)1e18;
const int INF=(1<<21);

int main(){
  int n;
  cin >> n;

  vector<pair<int, int>> e[n];
  priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int,int>>> pq;

  int d[n];
  bool visited[n];

  REP(i,n)d[i]=INF;
  REP(i,n)visited[i]=false;

  REP(i,n){
    int u,k;
    cin >> u >> k;

    REP(j,k){
      int v,c;
      cin >> v >> c;;
      e[i].push_back(make_pair(v,c));
    }
  }

  d[0]=0;
  visited[0]=true;

  pq.push(make_pair(0,0));
  while(!pq.empty()){
    int c=pq.top().first;
    int u=pq.top().second;
    pq.pop();

    visited[u] = true;
    if(d[u] < c)continue;

    REP(i,e[u].size()){
      int v = e[u][i].first;
      if(visited[v])continue;

      if(d[u] + e[u][i].second < d[v]){
        d[v] = d[u] + e[u][i].second;
        pq.push(make_pair(d[v], v));
      }
    }

  }

  REP(i,n){
    cout << i << " " << d[i] << endl;
  }


}