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<iomanip>
#include<limits>
#include<thread>
#include<utility>
#include<iostream>
#include<string>
#include<algorithm>
#include<set>
#include<map>
#include<vector>
#include<stack>
#include<queue>
#include<cmath>
#include<numeric>
#include<cassert>
#include<random>
#include<chrono>
using namespace std;
typedef unsigned long long int ull;
typedef long long int ll;
typedef pair<ll,ll> pll;
typedef pair<int,int> pi;
typedef pair<double,double> pd;
typedef pair<double,ll> pdl;
#define F first
#define S second
#define MK make_pair
const ll E=1e18+7;
const ll MOD=1000000007;




int main(){
    ll n;
    cin>>n;
    vector<vector<ll>> a(n,vector<ll>(n,E));
    for(int i=0;i<n;i++){
        a[i][i]=0;
    }
    for(int i=0;i<n;i++){
        ll u,k;
        cin>>u>>k;
        for(int t=0;t<k;t++){
            ll v,c;
            cin>>v>>c;
            a[i][v]=c;
        }
    }
    for(int k=0;k<n;k++){
        for(int i=0;i<n;i++){
            for(int t=0;t<n;t++){
                a[i][t]=min(a[i][t],a[i][k]+a[k][t]);
            }
        }
    }
    for(int i=0;i<n;i++){
        cout<<i<<" "<<a[0][i]<<endl;
    }
    
    
    return 0;
}

C++: #include<iostream>
#include<cmath>
#include<algorithm>
#include<cstdlib>
#include<cstring>

using namespace std;
typedef long long ll;
#define INF 2000000

ll graph[101][101],n;

void warshall_floyd(void);

int main(void){
  int u,k,v,c;

  cin >> n;

  for(int i=0;i<n;i++)
    for(int j=0;j<n;j++)
      graph[i][j]=INF;

  for(int i=0;i<n;i++)graph[i][i]=0;

  for(int i=0;i<n;i++){
    cin >> u >> k;
    while(k--){
      cin >> v >> c;
      graph[u][v]=c;
    }
  }

  warshall_floyd();

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

void warshall_floyd(void){
  for(int k=0;k<n;k++)
    for(int i=0;i<n;i++)
      for(int j=0;j<n;j++)
	graph[i][j]=min(graph[i][j],graph[i][k]+graph[k][j]);
  
}

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 < 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;
			}
		}
		//全ての頂点が到達済み
		if (v == -1) {
			break;
		}
		//集合に新たに頂点を追加
		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+100; i++) {
		for (int j = 0; j < V+100; j++) {
			cost[i][j] = INF;//iからjへの辺の重さ
		}
	}
	cin >> V;
	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>

using namespace std;

static const int MAX = 100;
static const int INF = (1 << 21);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

using namespace std;

int n, M[MAX][MAX];

void dijkstra() {
    int minv;
    int d[MAX], color[MAX];

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

    d[0] = 0;
    color[0] = GRAY;
    while (true) {
        minv = INF;
        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] != INF) {
                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] == INF ? -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] = INF;
        }
    }

    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 <stdio.h>
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];
int d[MAX];

void dijkstra(int s) {
    int p[n];
    int color[n];
    
    for(int i=0; i<n; i++) {
        color[i] = WHITE;
        d[i] = INFTY;
        p[i] = -1;
    }
    
    d[s] = 0;
    
    while(1) {
        int u;
        int mincost = INFTY;
        for (int i=0; i<n; i++) {
            if (color[i] != BLACK && d[i] < mincost) {
                mincost = d[i];
                u = i;
            }
        }
        
        if (mincost == INFTY) break;
        
        color[u] = BLACK;
        
        for (int v=0; v<=n; v++) {
            if (color[v] != BLACK && M[u][v] != INFTY) {
                if(d[u] + M[u][v] < d[v]) {
                    d[v] = d[u] + M[u][v];
                    p[v] = u;
                    color[v] = GRAY;
                }
            }
        }
    }
}

int main() {
    scanf("%d", &n);
    
    int u, k;
    for (int i=0; i<n; i++) {
        scanf("%d %d", &u, &k);
        for (int j=0; j<k; j++) {
            int tmp;
            scanf("%d", &tmp);
            M[u][tmp] = (tmp == -1) ? INFTY : tmp;
        }
    }
    
    dijkstra(0);
    
    for(int i=0; i<n; i++) {
        printf("%d %d\n", i, d[i]);
    }
    
    return 0;
}