Go: package main

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

const (
	white int = iota
	gray
	black
)

type node struct {
	id     int
	parent int
	edge   []int
	weight []int
	color  int
}

type graph struct {
	nodes    []node
	distance []int
}

var infty = 1 << 32
var null = -1

func constructgraph() *graph {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	n := nextInt(sc)

	g := &graph{make([]node, n), make([]int, n)}

	for i := 0; i < n; i++ {
		id := nextInt(sc)
		edges := nextInt(sc)
		n := node{}
		n.id = id
		n.edge = make([]int, edges)
		n.weight = make([]int, edges)
		n.color = white
		for j := 0; j < edges; j++ {
			to := nextInt(sc)
			w := nextInt(sc)
			n.edge[j] = to
			n.weight[j] = w
		}
		g.nodes[id] = n
	}
	return g
}

func nextInt(sc *bufio.Scanner) int {
	sc.Scan()
	v, _ := strconv.Atoi(sc.Text())
	return v
}

func (g *graph) preparedijkstra(s int) {
	for i := 0; i < len(g.nodes); i++ {
		g.nodes[i].color = white
		g.nodes[i].parent = null
		g.distance[i] = infty
	}
	g.distance[s] = 0
}

func (g *graph) dijkstra(s int) []int {
	g.preparedijkstra(s)

	for {
		var u int
		mincost := infty
		for i, d := range g.distance {
			if g.nodes[i].color != black && mincost > d {
				mincost = d
				u = i
			}
		}

		if mincost == infty {
			break
		}

		g.nodes[u].color = black

		for i, e := range g.nodes[u].edge {
			if g.nodes[e].color != black {
				if g.distance[e] > g.distance[u]+g.nodes[u].weight[i] {
					g.distance[e] = g.distance[u] + g.nodes[u].weight[i]
					g.nodes[e].parent = u
					g.nodes[e].color = gray
				}
			}
		}
	}
	return g.distance
}

func printShortestPath(d []int) {
	for i, v := range d {
		fmt.Printf("%d %d\n", i, v)
	}
}

func main() {
	g := constructgraph()
	d := g.dijkstra(0)
	printShortestPath(d)
}

C++: // https://onlinejudge.u-aizu.ac.jp/courses/lesson/1/ALDS1/all/ALDS1_12_B
#include <bits/stdc++.h>
using ll = long long;
using namespace std;

#define INFint 2e9+1

ll gcd(ll a, ll b) { return __gcd(a,b); }
ll lcm(ll a, ll b) { return a/gcd(a,b)*b; }

int main(){
// start
  struct edge {int to,cost;};
  int N;
  cin>>N;
  vector<vector<edge>> G(N,vector<edge>());
  for(int i(0);i<N;i++){
    int k,u;
    cin>>k>>u;
    for(int j(0);j<u;j++){
      int v,c;
      cin>>v>>c;
      G[k].push_back({v,c});
    }
  }
  vector<int> d(N);
  fill(d.begin(),d.end(),INFint);
  // first: cont, second: node number 
  priority_queue<pair<int,int>,vector<pair<int,int>>,greater<pair<int,int>>> q;
  int start = 0;
  d[start] = 0;
  q.push({0,start});

  while(!q.empty()){
    pair<int,int> p = q.top();q.pop();                                                  
    int v = p.second;
    //if (d[v] < p.first) continue;
    for (int i(0);i<int(G[v].size());i++){
      edge e = G[v][i];
      if (d[e.to] > d[v] + e.cost){
        d[e.to] = d[v] + e.cost;
        q.push({d[e.to],e.to});
      }
    }
  }
// end
  for(int i(0);i<N;i++){
    cout << i <<" " << d[i] << endl;
  }
  return 0;
}

C++: #include <bits/stdc++.h>
#define MAX_E 1000000
#define MAX_V 100000
#define INF 1e9
typedef long long ll;
using namespace std;
/*??????????????????????????? O(V*E)*/

//??????from????????????to???????????????cost??????
struct edge{int from, to, cost;};
edge es[MAX_E]; //???
ll d[MAX_V];   //???????????¢
int V,E;        //V???????????°???E????????°

//s???????????????????????????????????????????????¢????±???????.
void Bellman_Ford(int s){
  for(int i=0; i<V ;i++) d[i]=INF;
  d[s]=0;
  while(true){
    bool update=false;
    for(int i=0; i<E ;i++){
      edge e = es[i];
      if(d[e.from] != INF && d[e.to]> d[e.from] + e.cost){
	d[e.to] = d[e.from] + e.cost;
	update = true;
      }
    }
    if(!update) break;
  }
}

//true??????????????????????????¨??????
bool find_negative_loop(){
  memset(d,0,sizeof(d));

  for(int i=0; i<V ;i++){
    for(int j=0; j<E ;j++){
      edge e = es[j];
      if(d[e.to] > d[e.from] + e.cost){
	d[e.to] = d[e.from] + e.cost;
	
	//n??????????????´??°???????????????????????????????????¨?????????
	if(i == V-1) return true;
      }
    }
  }
  return false;
}

int main(){
  cin>>V;
  for(int i=0;i<V;i++){
    int u,k;
    cin>>u>>k;
    for(int j=0,v,c;j<k;j++){
      cin>>v>>c;
      es[E++]=(edge){u,v,c};
    }
  }
  
  for(int i=0;i<V;i++){
    Bellman_Ford(i);
    cout <<i<<" "<<d[0]<<endl;
  }
}

C++: #include <iostream>
#include <iomanip>
#include <string>
#include <stack>
#include <vector>
#include <math.h>
#include <stdio.h>
#include <algorithm>
#include <utility>
#include <functional>
#include <map>
#include <set>
#include <queue>
#include <list>
using namespace std;
using pii  = pair<int,int>;
using ll=long long;
using ld=long double;
#define stpr setprecision
#define pb push_back
#define mp make_pair
#define rep(i,n) for(int i=0;i<(n);++i)
#define REP(i,a,b) for(int i=(a);i<(b);++i)
#define crep(i) for(char i='a';i<='z';++i)
#define psortsecond(A,N) sort(A,A+N,[](const pii &a, const pii &b){return a.second<b.second;});
#define ALL(x) (x).begin(),(x).end()
#define endl '\n'
int ctoi(const char c){
  if('0' <= c && c <= '9') return (c-'0');
  return -1;
}
long long gcd(long long a, long long b){return (b == 0 ? a : gcd(b, a%b));}
long long lcm(long long a, long long b){return a*b/gcd(a,b);}
constexpr ll MOD=1000000007;
constexpr ld EPS=10e-8;
template<typename T> istream& operator>>(istream& is,vector<T>& v){for(auto&& x:v)is >> x;return is;}
template<typename T,typename U> istream& operator>>(istream& is, pair<T,U>& p){ is >> p.first; is >> p.second; return is;}
template<typename T,typename U> ostream& operator>>(ostream& os, const pair<T,U>& p){ os << p.first << ' ' << p.second; return os;}
template<class T> ostream& operator<<(ostream& os, vector<T>& v){
    for(auto i=begin(v); i != end(v); ++i){
        if(i !=begin(v)) os << ' ';
        os << *i;
    }
    return os;
}

ll N,A[107][107];
ll DKSTR[107],chek[107];

void dikstra(){
    DKSTR[0]=0;
    ll C=1,key=0;
    vector<pair<ll,ll>> V;
    while(C<N){
        chek[key]=1;
        V.clear();
        rep(i,N){
            DKSTR[i]=min(DKSTR[i],DKSTR[key]+A[key][i]);
            if(chek[i]==0){
                V.pb(mp(DKSTR[i],i));
            }
        }
        sort(ALL(V));
        while(1){
            key=V[0].second;
            C++;
            break;
        }
    }
}

int main(){
    ll X,Y,a,b;
    cin>>N;
    rep(i,N+1){
        rep(j,N+1){
            A[i][j]=MOD;
        }
        DKSTR[i]=MOD;
    }
    rep(i,N){
        cin >> X >> Y;
        rep(j,Y){
            cin >> a >> b;
            A[X][a]=b;
        }
    }
    dikstra();
    rep(i,N){
        cout << i << " " << DKSTR[i] << endl;
    }
}

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;
}