Go: package main

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

var sc = bufio.NewScanner(os.Stdin)

const T = 10000000

var n int
var A [101][101]int

func nextInt() int {
	sc.Scan()
	i, _ := strconv.Atoi(sc.Text())
	return i
}
func Shortestsearch() {
	var Minimum int
	var d, color [100]int
	var u int

	for i := 0; i < n; i++ {
		d[i] = T
		color[i] = 0
	}

	d[0] = 0
	color[0] = 1

	for {
		Minimum = T
		u = -1
		for i := 0; i < n; i++ {
			if Minimum > d[i] && color[i] != 2 {
				u = i
				Minimum = d[i]
			}
		}
		if u == -1 {
			break
		}
		color[u] = 2
		for j := 0; j < n; j++ {
			if color[j] != 2 && A[u][j] != T {
				if d[j] > d[u]+A[u][j] {
					d[j] = d[u] + A[u][j]
					color[j] = 1
				}
			}
		}
	}
	for i := 0; i < n; i++ {
		fmt.Printf("%d %d\n", i, d[i])
	}
}
func main() {
	sc.Split(bufio.ScanWords)
	n = nextInt()

	for i := 0; i < n; i++ {
		for j := 0; j < n; j++ {
			A[i][j] = T
		}
	}
	for i := 0; i < n; i++ {
		u := nextInt()
		k := nextInt()
		for j := 0; j < k; j++ {
			v := nextInt()
			c := nextInt()
			A[u][v] = c
		}
	}
	Shortestsearch()
}

C++: #include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<ll, ll> pll;
typedef vector<ld> vd;
typedef vector<ll> vll;
typedef vector<string> vstr;
typedef vector<vll> vvll;
typedef vector<vvll> vvvll;
typedef vector<pair<ll, ll>> vpll;
typedef priority_queue<ll, vector<ll>, greater<ll>> spqll;  // 小さい順に取り出し
typedef priority_queue<ll, vector<ll>, less<ll>> bpqll;     // 大きい順に取り出し

#define REP(i, n) for (ll i = 0; i < (ll)(n); i++)
#define FOR(i, a, b) for (ll i = (ll)a; i < (ll)b; i++)
#define IREP(i, v) for (auto i = (v).begin(); i != (v).end(); i++)
#define FI first
#define SE second
#define MP make_pair
#define MT make_tuple
#define PB push_back
#define TS to_string
#define NP next_permutation
#define ALL(v) (v).begin(), (v).end()
#define SZ(x) (ll) x.size()
#define SP(x) setprecision((ll)x)


ll INF = 1e9;
ll MOD = 1000000007;
ll LINF = 1e18;
ld EPS = 1e-9;
ld PI = M_PI;
vll dx = {1, 0, -1, 0, 1, -1, -1, 1};
vll dy = {0, 1, 0, -1, 1, 1, -1, -1};
ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a;} //最大公約数
ll lcm(ll a, ll b) { return a / gcd(a, b) * b;}     //最小公倍数

void yes(){ cout << "Yes" << endl;}
void no(){ cout << "No" << endl;}

//-----------------------------------------
class warshall_floyd{
  private:
    ll N; // 頂点数
    vvll dis; // iからjまでの最短距離
    ll inf = 1e18;

  public:
    warshall_floyd(ll n){
      N = n;
      dis.resize(N,vll(N));

      for(ll i=0;i<N;i++){
        for(ll j=0;j<N;j++){
          dis[i][j] = ( i == j ? 0 : inf );
        }
      }
    }

    // 辺の入力
    void in_edge(ll to, ll from, ll cost){
      dis[to][from] = cost;
    }

    // d[i][j]を埋める
    vvll main(){
      for(ll k=0;k<N;k++){
        for(ll i=0;i<N;i++){
          for(ll j=0;j<N;j++){
            dis[i][j] = min(dis[i][j], dis[i][k] + dis[k][j]);
          }
        }
      }
      return dis;
    }

    // 負の経路の検出
    bool mns_loop(){
      for(ll i=0;i<N;i++){
        if(dis[i][i] < 0) return true;
      }
      return false;
    }
};
//-----------------------------------------

int main(){
  cin.tie(0);
  ios::sync_with_stdio(false);
  cout << fixed << setprecision(10);

  ll n;
  cin >> n;
  warshall_floyd W(n);
  REP(i,n){
    ll v, k;
    cin >> v >> k;
    REP(j,k){
      ll a, b;
      cin >> a >> b;
      W.in_edge(v,a,b);
    }
  }
  vvll tmp = W.main();
  REP(i,n) cout << i << " " << tmp[0][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];

int 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;
}

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;
}

C++: //さっさと済ませられるところはさっさと済ましてしまう．ただし注意深く
#include <cstdio>
#include <iostream>
#define MAX_VERTEXES 100
#define NIL -1
#define INFTY 20000000// >100*100000

using namespace std;

//think easy make easy

int n;//num of vertexes(頂点)
int matrix_graph[MAX_VERTEXES+1][MAX_VERTEXES+1];//0オリジン
bool vertex_set[MAX_VERTEXES+1];///0オリジン
int current_mincost[MAX_VERTEXES+1];//現時点での各頂点への最小コスト
bool candidate[MAX_VERTEXES+1];//次にvertex_setに加える頂点の候補
int new_vertex;

void findNextVertex(){
	int min_tmp=INFTY;
	int next_tmp = NIL;
	
	for(int i=0;i<n;i++){
		for(int j=0;j<n;j++){
			if(i == new_vertex && vertex_set[j] == false){//わかりやすいプログラムほど処理もすくない.
				//無駄のないプログラムの方がわかりよい
				if(matrix_graph[i][j]+current_mincost[i] < current_mincost[j]
				   && matrix_graph[i][j] != NIL){
					   current_mincost[j]  = matrix_graph[i][j]+current_mincost[i];
					   candidate[j] = true;
				}
			}
		}
	}
	for(int i=0;i<n;i++){
		if(candidate[i] == true && current_mincost[i] < min_tmp){
			min_tmp = current_mincost[i];
			next_tmp = i;
		}
	}
	vertex_set[next_tmp] = true;
	candidate[next_tmp] = false;
	new_vertex = next_tmp;
}

int main(){
	scanf("%d",&n);

	int v_num;
	int k;//v_numの出次数

	for(int i=0;i<n;i++){
		for(int j=0;j<=n;j++){
			matrix_graph[i][j] = NIL;
		}
	}

	for(int i=0;i<n;i++){
		scanf("%d",&v_num);
		scanf("%d",&k);

		for(int j=0;j<k;j++){
			int v_num2;
			int cst;
			scanf("%d",&v_num2);
			scanf("%d",&cst);
			matrix_graph[v_num][v_num2] = cst;
		}
	}

	for(int i=0;i<n;i++){
		vertex_set[i] = false;
		current_mincost[i] = INFTY;
	}
	/*確認用
	for(int i=0;i<n;i++){
		for(int j=0;j<n;j++){
			if(j<n-1) printf("%d ",matrix_graph[i][j]);
			else printf("%d\n",matrix_graph[i][j]);
		}
	}
	*/

	for(int i=0;i<n;i++){
		candidate[i] = false;
	}

	vertex_set[0] = true;
	current_mincost[0] = 0;
	new_vertex = 0;

	for(int i=1;i<n;i++){
		//for(int j=0;j<n;j++){
			//cout <<" " <<vertex_set[j] ;
		//}
		//cout <<endl;
		findNextVertex();
	}


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


	return 0;
}