Go: package main

import (
	"strconv"
	"fmt"
	"bufio"
	"os"
)
const INF = 1 << 21
var scanner = bufio.NewScanner(os.Stdin)

func nextInt() int {
	scanner.Scan()
	i, e := strconv.Atoi(scanner.Text())
	if e != nil {
		panic(e)
	}
	return i
}


func main() {
	scanner.Split(bufio.ScanWords)
	n := nextInt()
	adj := make([][]int, n)
	for i := range adj {
		adj[i] = make([]int, n)
	}

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

	// for i := range adj {
	// 	fmt.Println(adj[i])
	// }

	dist := make([]int, n)
	prev := make([]int, n)
	visited := make([]bool, n)
	dijkstra := func(start int, size int) {
		for i := 0; i < size; i++ {
			dist[i] = INF
			prev[i] = -1
			visited[i] = false
		}
		dist[start] = 0
		for {
			u := -1
			tmp_min := INF
			for i := 0; i < size; i++ {
				if visited[i] == false && dist[i] < tmp_min {
					tmp_min = dist[i]
					u = i
				}
			}
			if u == -1 {
				break
			}
			visited[u] = true
			for i := 0; i < size; i++ {
				if adj[u][i] > 0 {
					w := adj[u][i]
					newlen := dist[u] + w
					if newlen < dist[i] {
						dist[i] = newlen
						prev[i] = u
					}
				}
			}
		}
	}
	dijkstra(0, n)
	for i, cost := range dist {
		fmt.Printf("%d %d\n", i, cost)
	}
}

C++: #include<iostream>
#include<vector>
#include<algorithm>
#define MAX_V 100
#define INF 1e9
using namespace std;
int cost[MAX_V][MAX_V];
int d[MAX_V];
bool used[MAX_V];
int V;
void dijkstra(int s)
{
	for (int i = 0; i < MAX_V; i++)

	{
		d[i] = INF;
		used[i] = false;
	}
	d[s] = 0;

	while (true)
	{
		int v = -1;
		for (int u = 0; u < V; u++)
		{
			if (!used[u] && (v == -1 || d[u] < d[v]))
			{
				v = u;
			}
		}
		if (v == -1)
		{
			break;
		}
		used[v] = true;

		for (int u = 0; u < V; u++)
		{
			d[u] = min(d[u], d[v] + cost[v][u]);
		}


	}
}
int main()
{
	for (int i = 0; i < V; i++)
	{
		int u;
		cin >> u;
		int k;
		cin >>  k;
		for (int j = 0; j < k; j++)

		{
			int v;
			cin >> v;
			int c;
			cin >> c;
			cost[u][v] = c;

		}
	}

	dijkstra(0);

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

}

C++: #include<iostream>
#include<vector>
#include<algorithm>
#include<queue>
#define N 100000
const int INF = 1 << 30; // > 10^9
int n;
using namespace std;
struct edge : vector<pair<int, int> > {
    void add_edge(int to, int cost) {
        push_back(pair<int, int>(to, cost));
    }
} info[N];
void bfs();
int hoge[N];
int main() {
    cin >> n;
    for (int i = 0; i < n; i++) {
        int u, k;
        cin >> u >> k;
        while (k--) {
            int v, c;
            cin >> v >> c;
            info[u].add_edge(v, c);
        }
    }
    bfs();
    for (int i = 0; i < n; i++) {
        cout << i << " " << hoge[i] << endl;
    }
}
void bfs() {
    fill_n(hoge, n, INF); //hoge ~ hoge + v <- INF
    queue<int> que;
    que.push(0);
    hoge[0] = 0;
    while (!que.empty()) {
        int p = que.front();
        que.pop();
        for (int i = 0; i < info[p].size(); i++) {
            if (info[p][i].second + hoge[p] < hoge[info[p][i].first]) {
                que.push(info[p][i].first);
                hoge[info[p][i].first] = info[p][i].second + hoge[p];
            }
        }
    }
    
}

C++: #include <stdio.h>
#include <vector>
#include <utility>
#define rep(i, n) for(int i = 0; i < n; ++i)
using namespace std;

int main(void) {
  int n, ans = 0;
  scanf("%d", &n);
  int dis[n];
  rep(i, n) dis[i] = 10e7;
  dis[0] = 0;
  vector< pair<int, int> > vec[n];
  rep(i, n) {
    int u, k;
    scanf("%d%d", &u, &k);
    rep(j, k) {
      int c, v;
      scanf("%d%d", &v, &c);
      pair<int, int> p = make_pair(v, c);
      vec[u].push_back(p);
    }
  }
  /*rep(i, n) {
    vector< pair<int, int> >::iterator it;
    for(it = vec[i].begin(); it != vec[i].end(); ++it) printf("%d:%d ", (*it).first, (*it).second);
    printf("\n");
  }*/
  rep(i, n - 1) {
    rep(j, n) {
      vector< pair<int, int> >::iterator it;
      for(it = vec[j].begin(); it != vec[j].end(); ++it) {
        if(dis[(*it).first] > dis[j] + (*it).second) dis[(*it).first] = dis[j] + (*it).second;
      }
    }
    /*rep(j, n) printf("%d ", dis[j]);
    printf("\n");*/
  }
  rep(i, n) printf("%d %d\n", i, dis[i]);
  return 0;
}

C++: #include <iostream>
#include <stdio.h>
#include <vector>

#define inf 500000
using namespace std;

int main() {
    int n, tmp, tweight, kazu;
    int g[100][100] = {};//与えられるグラフ
    cin >> n;

    //初期化
    int d[100] = {};
    for (int i = 1; i < n; ++i) {
        d[i] = inf;
    }
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < n; ++j) {
            g[i][j] = -1;
        }
    }
    for (int i = 0; i < n; ++i) {
        g[i][i] = 0;
    }

    //入力を受け取る
    for (int i = 0; i < n; ++i) {
        cin >> tmp;
        cin >> kazu;
        for (int j = 0; j < kazu; ++j) {
            cin >> tmp >> tweight;
            g[i][tmp] = tweight;
        }
    }
    /*
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < n; ++j) {
            cout << g[i][j] << " ";
        }
        cout << endl;
    }
     */

    for (int k = 0; k < n; ++k) {

        for (int i = 0; i < n; ++i) { // i 今最短経路を求めているノード
            /*
            for (int l = 0; l < n; ++l) {
                cout << d[i] << " ";
            }
            cout << endl;
             */
            for (int j = 0; j < n; ++j) { // j k の組でその２点間の重み
                //cout << i << " " << d[i] << " " << d[j] << " " << g[j][i] << endl;
                if (d[i] > d[j] + g[j][i] && g[j][i] != -1) {
                    d[i] = d[j] + g[j][i];

                }
            }
        }

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

    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, -1));
    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) {
                if (G[i][j] < 0)
                    continue;
                int w = G[i][j] + d[i];
                if (!visited[j] && 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++: #include<stdio.h>
#include<stdlib.h>

#define rep( i ,end ) for( int i = 0 ; i < end ; ++i )
#define Nmax 100
#define INF ( INT_MAX / 10 )

int Node[ Nmax ][ Nmax ] ;

int min( int a ,int b )
{
	return a > b ? b : a ;
}

void Init( int ( *NODE )[ Nmax ] ,int N )
{
	rep( i ,N )
	{
		rep( j ,N )
		{
			NODE[ i ][ j ] = ( i == j ) ? 0 : INF ;
		}
	}
}



int main( void )
{
	int N ,V ,K ;
	int v ,cost ;
	scanf( "%d" ,&N ) ;

	Init( Node ,N ) ;

	rep( i ,N )
	{
		scanf( "%d %d" ,&V ,&K ) ;

		rep( j ,K )
		{
			scanf( "%d %d" ,&v ,&cost ) ;

			Node[ V ][ v ] = cost ;
		}
	}

	rep( u ,N )
	{
		rep( i ,N )
		{
			rep( j ,N )
			{
				Node[ i ][ j ] = min( Node[ i ][ j ] ,Node[ i ][ u ] + Node[ u ][ j ] ) ;
			}
		}
	}

	rep( u ,N )
	{
		printf( "%d %d\n" ,u ,Node[ 0 ][ u ] ) ;
	}

	return 0 ;
}