Go: package main

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

const BIG_COST = 200000

const (
	ST_NOT_YET = iota
	ST_JOINED
)

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	nNodes := scanInt(sc)

	costs := make([][]int, nNodes)
	graph := make([][]int, nNodes)

	states := make([]int, nNodes)
	costSums := make([]int, nNodes)

	for i := 0; i < nNodes; i++ {
		costs[i] = make([]int, nNodes)
		costSums[i] = BIG_COST
	}

	for i := 0; i < nNodes; i++ {
		u := scanInt(sc)
		k := scanInt(sc)
		graph[u] = make([]int, k)
		for d := 0; d < k; d++ {
			v := scanInt(sc)
			graph[u][d] = v
			costs[u][v] = scanInt(sc)
		}
	}

	costSums[0] = 0
	for {
		minCost := BIG_COST
		var u int

		for i, cost := range costSums {
			if states[i] != ST_JOINED && cost < minCost {
				minCost = cost
				u = i
			}
		}

		if minCost == BIG_COST {
			break
		}

		states[u] = ST_JOINED

		for _, v := range graph[u] {
			cost := minCost + costs[u][v]
			if cost < costSums[v] {
				costSums[v] = cost
			}
		}
	}

	w := bufio.NewWriter(os.Stdout)
	for i, cost := range costSums {
		fmt.Fprintf(w, "%d %d\n", i, cost)
	}
	w.Flush()
}

func scanInt(sc *bufio.Scanner) int {
	sc.Scan()
	v, _ := strconv.Atoi(sc.Text())
	return v
}

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][v]+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<bits/stdc++.h>
using namespace std;

typedef pair<int, int> P;
const int M = 1000000007;

vector<int> dijkstra(int s, vector<vector<P>> edge) {
    int n = edge.size();
    vector<int> dist(n, M);
    priority_queue<P, vector<P>, greater<P>> q;
    dist[s] = 0;
    q.push(P(0, s));
    while (!q.empty()) {
        P p = q.top();
        q.pop();
        int d = p.first;
        for (auto& e : edge[p.second]) {
            if (dist[e.second] > p.first + e.first) {
                dist[e.second] = p.first + e.first;
                q.push(P(p.first + e.first, e.second));
            }
        }
    }
    return dist;
}


int main() {
    int n;
    cin >> n;
    vector<vector<P>> edge(n);
    for (int i = 0; i < n; ++i) {
        int u, k;
        cin >> u >> k;
        if (i != u) exit(1);
        for (int j = 0; j < k; ++j) {
            int v, c;
            cin >> v >> c;
            edge[i].push_back(P(c, v));
        }
    }
    vector<int> d = dijkstra(0, edge);
    for (int i = 0; i < n; ++i) {
        cout << i << " " << d[i] << "\n";
    }
    return 0;
}

C++: #include<iostream>
using namespace std;
#define N 105
#define INF 1<<21
int n;
int a[N][N];
int d[N],p[N];
int color[N];
void dijksla(){
	int minv;
	for (int i = 0;i < n;i++){
		d[i] = INF;
		color[i] = 0;
	}
	d[0] = 0;
	while (1){
		minv = INF;
		int u = -1;
		for (int i = 0;i < n;i++){
			if (minv > d[i] && color[i] != 1){
				u = i;
				minv = d[i];
			}
		}
		if (u == -1) break;
		color[u] = 1;
		for (int v = 0;v < n;v++){
			if (color[v] == 0 && a[u][v] != INF){
				if (d[v] > d[u] + a[u][v]){
					d[v] = d[u] + a[u][v];
				}
			}
		}
	}
	for (int i = 0;i < n;i++){
		if (d[i] == INF){
			cout << i << " -1" << endl;
		}
		else{
			cout << i << " " << d[i] << endl;
		}
	}
}

int main()
{
	cin >> n;
	for (int i = 0;i < n;i++){
		for (int j = 0;j < n;j++){
			a[i][j] = INF;
		}
	} 
	int x,m,y,q;
	for (int i = 0;i < n ;i++){
		cin >> x >> m;
		for (int j = 0;j < m;j++){
			cin >> y >> q;
			a[x][y] = q;
		}
	}
	dijksla();
	return 0;
 }

C++: #include <bits/stdc++.h>
using namespace std;

int n;
int MAXIMUM=100;
int M[100][100];
int INF = 123456789;
// W:未訪問
// G:訪問する候補
// B:訪問済み
int W=0,G=1,B=2;
int dijkstra(){
  int u,minv;
  int d[MAXIMUM],color[MAXIMUM];
  // d[n]:Tに属する頂点と V - T に属する頂点をつなぐ辺の中で重みが最小の辺の重みを記録
  // p[i]: 頂点iからコスト最小となる親の頂点
  //初期化
  for(int i=0;i<n;i++){
    d[i]=INF;
    color[i]=W;
  }

  d[0]=0;
  color[0] = G;

  while (1) {
    minv = INF;
    u = -1;
    //訪問済みでない頂点の中で最もコストが低い辺を探す
    for(int i=0;i<n;i++){
      if(minv>d[i] && color[i]!=B){
        u=i;
        minv=d[i];
      }
    }
    // 頂点が見つからなかったら終了
    if(u==-1) break;
    // 頂点を訪問済に
    color[u] = B;
    //訪問済みでないかつ辺がつながっている頂点の中でコストが最小の辺を選択
    for(int v=0;v<n;v++){
      if(color[v]!=B && M[u][v]!=INF){
        if(d[v]>M[u][v] + d[u]){
          d[v] =M[u][v]+d[u];
          color[v]=G;
        }
      }
    }
  }

  for(int i=0;i<n;i++){
    if(d[i]!=INF) cout<<i<<" "<<d[i]<<endl;
    else cout<<i<<" "<<-1<<endl;
  }
}

int main(){
  cin>>n;
  for(int i=0;i<n;i++){
    for(int j=0;j<n;j++){
      M[i][j]=INF;
    }
  }

  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;
      M[u][v]=c;
    }
  }

  dijkstra();

}

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++: #include <climits>
#include <functional>
#include <iostream>
#include <queue>
#include <utility>
#include <vector>
using namespace std;

int main() {
	int n, u, k, v, c;
	cin >> n;
	vector<vector<pair<int, int>>> a(n);
	for (int i = 0; i < n; ++i) {
		cin >> u >> k;
		for (int j = 0; j < k; ++j) {
			cin >> v >> c;
			a[u].emplace_back(v, c);
		}
	}
	priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> b;
	b.emplace(0, 0);
	vector<bool> d(n);
	vector<int> e(n, INT_MAX);
	e[0] = 0;
	while (!b.empty()) {
		pair<int, int> f = b.top();
		b.pop();
		d[f.second] = true;
		for (int i = 0; i < a[f.second].size(); ++i) {
			if (!d[a[f.second][i].first]) {
				if (a[f.second][i].second + e[f.second] < e[a[f.second][i].first]) {
					e[a[f.second][i].first] = a[f.second][i].second + e[f.second];
					b.emplace(e[a[f.second][i].first], a[f.second][i].first);
				}
			}
		}
	}
	for (int i = 0; i < n; ++i) cout << i << ' ' << e[i] << endl;
}