Go: package main

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

func getScanner(fp *os.File) *bufio.Scanner {
	scanner := bufio.NewScanner(fp)
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 500001), 500000)
	return scanner
}

func getNextString(scanner *bufio.Scanner) string {
	scanner.Scan()
	return scanner.Text()
}

func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}

func main() {
	fp := os.Stdin
	if len(os.Args) > 1 {
		fp, _ = os.Open(os.Args[1])
	}

	scanner := getScanner(fp)
	writer := bufio.NewWriter(os.Stdout)

	n := getNextInt(scanner)

	g := makeGraph(n)
	for i := 0; i < n; i++ {
		u := getNextInt(scanner)
		k := getNextInt(scanner)
		for ii := 0; ii < k; ii++ {
			v := getNextInt(scanner)
			c := getNextInt(scanner)
			g[u][v] = c
		}
	}

	ans := make([]int, n)
	im := make(IntMap, 1)
	im.increment(0)
	for len(im) < n {
		min := 1 << 30
		x := -1
		for u := range im {
			for v := 0; v < n; v++ {
				if im.get(v) != 0 {
					continue
				}
				if min > ans[u]+g[u][v] {
					min = ans[u] + g[u][v]
					x = v
				}
			}
		}
		im.increment(x)
		ans[x] = min
	}

	for i := 0; i < n; i++ {
		fmt.Fprintln(writer, fmt.Sprintf("%d %d", i, ans[i]))
	}
	writer.Flush()
}

func makeGraph(n int) [][]int {
	g := make([][]int, n)
	for i := 0; i < n; i++ {
		g[i] = make([]int, n)
		for ii := 0; ii < n; ii++ {
			g[i][ii] = 1 << 30
		}
	}

	return g
}

// IntMap ...
type IntMap map[int]int

func (m IntMap) get(key int) int {
	if _, ok := m[key]; ok {
		return m[key]
	}
	return 0
}
func (m IntMap) increment(key int) {
	if _, ok := m[key]; ok == false {
		m[key] = 0
	}
	m[key]++
}

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,v,c,u;
 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 <vector>
#include <iostream>
#include <algorithm>
#include <limits>

using namespace std;
using graph = vector<vector<int>>;


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

    graph G(n, vector<int>(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][v] = c;
        }
    }

    // Dijkstra's algorithm
    vector<int> d(n, -1);
    vector<bool> visited(n, false);

    d[0] = 0;
    visited[0] = true;
    while (1) {
        int u = -1;
        int v = -1;
        int minw = numeric_limits<int>::max();
        for (int i = 0; i < n; ++i) {
            if (!visited[i])
                continue;
            for (int j = 0; j < n; ++j) {
                int w = G[i][j] + d[i];
                if (!visited[j] && 0 < w && w < minw) {
                    u = i;
                    v = j;
                    minw = w;
                }
            }
        }
        if (v < 0) {
            break;
        }
        d[v] = minw;
        visited[v] = true;
    }

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

    return 0;
}

C++: //Single_Source_Shortest_Path_I
/*
5
0 3 2 3 3 1 1 2
1 2 0 2 3 4
2 3 0 3 3 1 4 1
3 4 2 1 0 1 1 4 4 3
4 2 2 1 3 3
*/
#include <iostream>
using namespace std;
static const int INF = (1<<21);

int main(){

    int n;
    cin>>n;
    int M[100][100];
    for(int i=0;i<100;i++){
        for(int j=0;j<100;j++){
            if(i==j)
                M[i][j]=0;
            else
                M[i][j]=INF;
        }
    }
    int w,m,v,u;
    for(int i=0;i<n;i++){
        cin>>u>>m;
        for(int j=0;j<m;j++){
            cin>>v>>w;
            M[u][v]=w;
        }
    }
    for(int k=0;k<n;k++){
        for(int i=0;i<n;i++){
            for(int j=0;j<n;j++){
                if(M[i][j]>M[i][k]+M[k][j])
                    M[i][j]=M[i][k]+M[k][j];
            }
        }
    }
    for(int i=0;i<n;i++){
        cout<<i<<" "<<M[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];

void dik(){
int min;
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){
min=INFTY;
int u=-1;
for(int i=0;i<n;i++){
if(min>d[i]&&color[i]!=BLACK){
u=i;
min=d[i];
}
}
if(u==-1)break;
color[u]=BLACK;
for(int v=0;v<n;v++){
if(color[v]!=BLACK&&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;
}
}

dik();

return 0;
}

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

typedef pair<int, int> P;
const int INF = 1000000000;

struct edge {
    int to, cost;
};

int main() {
    int n;
    cin >> n;
    vector<edge> G[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;
            edge e = {v, c};
            G[u].push_back(e);
        }
    }
    vector<int> d(n, INF);
    d[0] = 0;
    priority_queue< P, vector<P>, greater<P> > que;
    que.push(P(0, 0));

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

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