Go: package main

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

func main() {
	r := bufio.NewReader(os.Stdin)

	var n int
	fmt.Fscan(r, &n)
	cs := make([]map[int]int, n) // []v_i -> c_i
	for h := 0; h < n; h++ {
		var u, k int
		fmt.Fscan(r, &u, &k)
		m := make(map[int]int)
		for i := 0; i < k; i++ {
			var v, c int
			fmt.Fscan(r, &v, &c)
			m[v] = c
		}

		cs[u] = m
	}

	q := make(map[int]int)
	q[0] = 0
	visited := make(map[int]struct{})
	out := make([]int, n)

	for len(q) > 0 {
		u := top(q)
		for uu, c := range cs[u] {
			// Consider the connection between u and uu.
			if _, ok := visited[uu]; ok {
				continue
			}
			if d, ok := q[uu]; !ok || d > q[u]+c {
				q[uu] = q[u] + c
			}
		}

		out[u] = q[u]
		delete(q, u)
		visited[u] = struct{}{}
	}

	for u, d := range out {
		fmt.Println(u, d)
	}
}

func top(q map[int]int) int {
	minu := -1
	min := -1
	for u, d := range q {
		if min < 0 || d < min {
			minu = u
			min = d
		}
	}

	return minu
}

C++: #include <iostream>
#include <cstdlib>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <set>
#include <string>
#include <cmath>
using namespace std;

#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define REP(i, k, n) for (int i = (int)(k); i < (int)(n); i++)
#define rrep(i, n) for (int i = (int)(n)-1; i >= 0; i--)
#define rREP(i, k, n) for (int i = (int)(n)-1; i >= k; i--)

#define debug(x) cerr<<#x<<": "<<x<<'\n'

#define fi first
#define se second

#define vi vector<int>
#define pb push_back
#define mp make_pair

#define pcnt __builtin_popcount

typedef long long ll;

const int inf = 100100100;
const int MOD = (int)1e9 + 7;
const double EPS = 1e-9;
int G[110][110] = {};
int d[110] = {};
int main(){
    int n;
    cin >> n;
    memset(G,-1,sizeof(G));
    rep(i,n){
        int t,m;
        cin >> t >> m;
        rep(j,m){
            int a,b;
            cin >> a >> b;
            G[t][a] = b;
        }
    }

    rep(i,n) d[i] = 900010000;
    d[0] = 0;
    while(true){
        bool update = false;
        rep(i,n){
            rep(j,n){
                if(i==j) continue;
                if(G[i][j] != -1 && d[i] + G[i][j] < d[j]){
                    d[j] = d[i]+G[i][j];
                    update = true;
                }
            }
        }
        if(!update) break;
    }

    rep(i,n){
        cout << i << " " << d[i] << endl;
    }

    return 0;
}

C++: #include <bits/stdc++.h>
const int INF = 500000;
using namespace std;

int main(void){
  bool used[100];
  int n, G[100][100];
  cin >> n;
  for(int i=0; i < 100; i++){
    used[i] = false;
    for(int j=0; j < 100; j++){
      G[i][j] = INF;
    }
  }
  for(int i=0; i < n; i++){
    int vtmp, k;cin >> vtmp >> k;
    for(int j=0; j < k; j++){
      int v, c; cin >> v >> c;
      G[vtmp][v] = c;   
    }
  }

  int d[100];
  for(int i=0; i < n; i++){
    d[i] = INF;
  }
  d[0] = 0;

  for(int i=0; i < n; i++){
    int mind = INF;
    int minind = -1;
    for(int j=0; j < n; j++){
      if(used[j] == false && d[j] < mind){
        mind = d[j]; minind = j;
      }
    }
    if(minind == -1) break;
    used[minind] = true;
    for(int j=0; j < n; j++){
      if(used[j] == false && G[minind][j] != INF){
        if(d[minind] + G[minind][j] < d[j]){
          d[j] = d[minind] + G[minind][j];
        }
      }
    }
  }
  for(int i=0; i < n; i++){
    cout << i << " " << d[i] << endl;
  }

  return 0;
}

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

using namespace std;
typedef long long ll;
//typedef unsigned long long ll;

#define rep(i, n) for (int i = 0; i < (n); ++i)
//#define rep(i, n) for (ll i = 0; i < (n); ++i)
//#define sz(x) ll(x.size())
//typedef pair<ll, int> P;
//typedef pair<ll, ll> P;
//const double INF = 1e10;
const ll INF = LONG_LONG_MAX / 10;
//const ll INF = 1e15;
const ll MINF = LONG_LONG_MIN;
//const int INF = INT_MAX / 10;
#define cmin(x, y) x = min(x, y)
#define cmax(x, y) x = max(x, y)

bool contain(set<int> &s, int a) { return s.find(a) != s.end(); }

//ifstream myfile("C:\\Users\\riku\\Downloads\\0_00.txt");
//ofstream outfile("log.txt");
//outfile << setw(6) << setfill('0') << prefecture << setw(6) << setfill('0') << rank << endl;
// std::cout << std::bitset<8>(9);

typedef pair<double, double> P;

void print_line(vector<int> &line) {
    if (line.size() == 0ll) {
        cout << endl;
        return;
    }
    for (ll i = 0; i < line.size(); i++) {
        cout << line[i];
        if (i == line.size() - 1) cout << endl;
        else cout << ' ';
    }
}


typedef priority_queue<long long, vector<long long>, greater<long long>> PQ_ASK;
const int mod = 1000000007;

void warshall_floyd(int n, vector<vector<ll>> &d) {
    for (int k = 0; k < n; k++) {       // 経由する頂点
        for (int i = 0; i < n; i++) {    // 始点
            for (int j = 0; j < n; j++) {  // 終点
                d[i][j] = min(d[i][j], d[i][k] + d[k][j]);
            }
        }
    }
}

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

    vector<vector<ll>> distances(n, vector<ll>(n, INF));
    rep(i, n) distances[i][i] = 0;
    rep(i, n) {
        int j, k;
        cin >> j >> k;

        rep(l, k) {
            int u, c;
            cin >> u >> c;
            distances[j][u] = c;
        }
    }

    warshall_floyd(n, distances);

    rep(i, n) cout << i << ' ' << distances[0][i] << endl;

}

C++: #include<iostream>
#define N 101
#define INF 1<<21
using namespace std;

int A[N][N];
int n;
int visited[N];
int d[N];
int p[N];

void dijkstra(int b){
    d[b]=0;
    p[b]=-1;
    int node=-1;
    int minval=INF;
    while(1){
        node=-1;
        minval=INF;
        for(int i=0;i<n;i++){
            if(visited[i]==true) continue;
            if(d[i]<minval){
                node=i;
                minval=d[i];
            }
        }
        if(node==-1) break;
        visited[node]=true;
        for(int e=0;e<n;e++){
            if(A[node][e]==INF || visited[e]==true) continue;
            if(d[e]>d[node]+A[node][e]){
                d[e]=d[node]+A[node][e];
            }
        }
    }
}

void init(){
    int k;
    int b,e,val;
    cin>>n;
    for(int i=0;i<n;i++){
        visited[i]=false;
        d[i]=INF;
        p[i]=-1;
        for(int j=0;j<n;j++){
            A[i][j]=INF;
        }
    }
    for(int i=0;i<n;i++){
        cin>>b>>k;
        for(int j=0;j<k;j++){
            cin>>e>>val;
            A[b][e]=val;
        }
    }
}

int main(){
    init();

    dijkstra(0);

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

C++: #include <utility>
#include <vector>
#include <queue>
#include <functional>
#include <cassert>

using namespace std;

class Dijkstra {
#define MAX_V 101
  typedef pair<int, int> P;

private:
  const int INF = 1e9 + 10;
  struct Edge {
    int to, cost;
    Edge(int to, int cost): to(to), cost(cost) { }
  };

  int V;
  vector<Edge> G[MAX_V];

public:

  Dijkstra(int V): V(V) { 
    if (V >= MAX_V) {
      assert(false);
    }
  }

  void AddEdge(int from, int to, int cost) {
    G[from].push_back(Edge(to, cost));
  }

  vector<int> Solve(int s) {
    priority_queue<P, vector<P>, greater<P>> que;
    vector<int> d(V, INF);
    d[s] = 0;
    que.push(P(0, s));

    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));
        }
      }
    }

    return d;
  }
};

#include <iostream>


int main() {
  int n;
  cin >> n;
  Dijkstra dijkstra(n);
  for (int i = 0; i < n; i++) {
    int u, k;
    cin >> u >> k;
    for (int j = 0; j < k; j++) {
      int t, c;
      cin >> t >> c;
      dijkstra.AddEdge(u, t, c);
    }
  }

  vector<int> d = dijkstra.Solve(0);

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

  return 0;
}