Go: package main

import (
	"bufio"
	"bytes"
	"fmt"
	"io"
	"os"
	"strconv"
	"strings"
)

const (
	INFTY = 1 << 21
	NIL   = -1
)

const (
	WHITE = iota
	GRAY
	BLACK
)

type Graph [][]int

func (g *Graph) dikstra(n int) string {
	var (
		u, minv = 0, 0
	)

	d := make([]int, n)
	color := make([]int, n)

	for i := 0; i < n; i++ {
		d[i] = INFTY
		color[i] = WHITE
	}
	d[0] = 0
	color[0] = GRAY

	for {
		minv = INFTY
		u = -1
		for 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 v := 0; v < n; v++ {
			if color[v] != BLACK && (*g)[u][v] != INFTY {
				if d[v] > d[u]+(*g)[u][v] {
					d[v] = d[u] + (*g)[u][v]
					color[v] = GRAY
				}
			}
		}
	}

	var out bytes.Buffer
	for i := 0; i < n; i++ {
		out.WriteString(fmt.Sprintf("%d ", i))
		if d[i] == INFTY {
			out.WriteString(fmt.Sprintf("%d\n", -1))
			continue
		}
		out.WriteString(fmt.Sprintf("%d\n", d[i]))
	}

	return strings.TrimRight(out.String(), "\n")
}

func answer(reader io.Reader) string {
	sc := bufio.NewScanner(reader)
	sc.Split(bufio.ScanWords)

	sc.Scan()
	n, _ := strconv.Atoi(sc.Text())

	g := make(Graph, n)
	for i := 0; i < n; i++ {
		g[i] = make([]int, n)
		for j := 0; j < n; j++ {
			g[i][j] = INFTY
		}
	}

	for i := 0; i < n; i++ {
		sc.Scan()
		u, _ := strconv.Atoi(sc.Text())
		sc.Scan()
		k, _ := strconv.Atoi(sc.Text())

		for j := 0; j < k; j++ {
			sc.Scan()
			v, _ := strconv.Atoi(sc.Text())
			sc.Scan()
			c, _ := strconv.Atoi(sc.Text())

			g[u][v] = c
		}
	}

	return g.dikstra(n)
}

func main() {
	fmt.Println(answer(os.Stdin))
}

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;
        }
       }
     }
  }
    if(u == -1) break;
    color[u] = BLACK;
   for(int v = 0; v < n; v++){
    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,v,c,u;
 for(int i = 0;i < n; i++){
  cin >> u >>c;
  M[u][v] = c;
  }
 }
  dijkstra();
   return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
using ll = long long;
using vi = vector<int>;
using vvi = vector<vi>;
using vll = vector<ll>;

#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define WHITE 0
#define VISITED 1
#define CANDIDATE 2

int dks(vvi &a, vi &d, vi &s, vi &p) {
  int total = 0, n = (int)a.size();
  while (true) {
    int min_cost = INT_MAX, u;
    rep(i, n) {
      if (s[i] != VISITED && d[i] < min_cost) {
        min_cost = d[i];
        u = i;
      }
    }

    if (min_cost == INT_MAX) break;

    s[u] = VISITED;
    if (p[u] != -1) total += a[p[u]][u];

    rep(v, n) {
      if (s[v] != VISITED && a[u][v] != -1) {
        if (d[u] + a[u][v] < d[v]) {
          d[v] = d[u] + a[u][v];
          p[v] = u;
          s[v] = CANDIDATE;
        }
      }
    }
  }
  
  return total;
}

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

  vvi g(n, vi(n, -1));
  rep(i, n) {
    int u, k;
    cin >> u >> k;

    rep(j, k) {
      int v, c;
      cin >> v >> c;

      g[u][v] = c;
    }
  }
  
  vi d(n, INT_MAX), s(n, WHITE), p(n, -1);
  d[0] = 0;
  
  dks(g, d, s, p);
  
  rep(i, n) printf("%d %d\n", i, d[i]);
}

C++: #include <iostream>
using namespace std;
static const int MAX = 100;
static const int INFTY = (1<<21);
static const int WHITH = 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] = WHITH;
  }

  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 N = 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[N][N],d[N];

void dijkstra(int s){
	int color[N],p[N];
	for(int i=0;i<n;i++){
		color[i] = WHITE;
		d[i] = INFTY;
	}
	d[s] = 0;
	p[s] = -1;

	int u;
	while(1){
		int minv = INFTY;
		for(int i=0;i<n;i++){
			if(color[i]!=BLACK&&d[i]!=INFTY){
				if(d[i] < minv){
					minv = d[i];
					u = i;
				}
			}
		}
		if(minv == INFTY)break;
		color[u] = BLACK;
		for(int i=0;i<n;i++){
			if(color[i]!=BLACK&&M[u][i]!=INFTY){
				if(d[u]+M[u][i] < d[i]){
					d[i] = d[u]+M[u][i];
					p[i] = u;
				}
			}
		}
	}
}

int main(){
	cin >> n;
	int e,u,k,c,v;
	for(int i=0;i<n;i++){
		for(int j=0;j<n;j++){
			M[i][j] = INFTY;
		}
	}
	for(int i=0;i<n;i++){
		cin >> u >> k;
		for(int j=0;j<k;j++){
			cin >> v >> c;
			M[i][v] = c;
		}
	}
	dijkstra(0);
	for(int i=0;i<n;i++){
		cout << i << " " << d[i] << endl;
	}
	return 0;
}