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<cstdio>
static const int kMaxVertices = 100;
static const int kInfinity = 100010;
static int Adjacency_matrix[kMaxVertices][kMaxVertices];

void InitializeCostMatrix(int nmbr_of_rows, int nmbr_of_columns){
	for (int row = 0; row < nmbr_of_rows; ++row) {
		for (int column = 0; column < nmbr_of_columns; ++column)
			Adjacency_matrix[row][column] = kInfinity;
	}
}

void Dijkstra(int n){
	bool has_not_been_discovered[kMaxVertices];
	int lowest_cost_route[kMaxVertices];
	int parent[kMaxVertices];
	for (int i = 0; i < n; ++i)	{
		has_not_been_discovered[i] = true;
		lowest_cost_route[i] = kInfinity;
	}
	lowest_cost_route[0] = 0;
	parent[0] = -1;

	while(true) {
		int mincost = kInfinity;
		int vertex_to_add;
		for (int i = 0; i < n; ++i)	{
			if(has_not_been_discovered[i] && lowest_cost_route[i] < mincost){
				mincost = lowest_cost_route[i];
				vertex_to_add = i;
			}
		}

		if(mincost == kInfinity)
			break;

		has_not_been_discovered[vertex_to_add] = false;
		int vertex_added = vertex_to_add;

		for (int i = 0; i < n; ++i)	{
			if(has_not_been_discovered[i] && lowest_cost_route[vertex_added] + Adjacency_matrix[vertex_added][i] < lowest_cost_route[i]) {
				lowest_cost_route[i] = lowest_cost_route[vertex_added] + Adjacency_matrix[vertex_added][i];
				parent[i] = vertex_added;
			}
		}
	}
	for (int i = 0; i < n; ++i)
		printf("%d %d\n", i, lowest_cost_route[i]);
}

int main() {
	int nmbr_of_vertices;
	scanf("%d", &nmbr_of_vertices);
	InitializeCostMatrix(nmbr_of_vertices, nmbr_of_vertices);
	for (int vertex_from_i = 0; vertex_from_i < nmbr_of_vertices; ++vertex_from_i) {
		int vertex_from_id, degree_out;
		scanf("%d %d", &vertex_from_id, &degree_out);
		for (int vertex_to_i = 0; vertex_to_i < degree_out; ++vertex_to_i) {
			int vertex_to_id, cost;
			scanf("%d %d", &vertex_to_id, &cost);
			Adjacency_matrix[vertex_from_id][vertex_to_id] = cost;
		}
	}
	Dijkstra(nmbr_of_vertices);
	return 0;
}

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

int main()
{
    int n, m, i, j, a, w;
    int* adj[100];
    int* dist[100];
    cin >> n;
    for(i = 0; i < n; i++){
        cin >> i >> m;
        adj[i] = new int [m + 1];
        dist[i] = new int [m + 1];
        for(j = 0; j < m; j++){
            cin >> a >> w;
            adj[i][j] = a;
            dist[i][j] = w;
        }
        adj[i][m] = -1;
        dist[i][m] = -1;
    }
    int *d, *prev, *Q;
    d = new int [n];
    prev = new int [n];
    Q = new int [n];
    for(i = 0; i < n; i++){ d[i] = 200000; prev[i] = -1; Q[i] = i; }
    int rest = n;
 
    int u, v, min;
    d[0] = 0;
    while(rest > 0){
        min = 200000;
        for(i = 0; i < n; i++){
            if(min > d[i] && Q[i] >= 0){ min = d[i]; u = i; }
        }
        Q[u] = -1;
        rest--;

        for(j = 0; adj[u][j] >= 0; j++){
            v = adj[u][j];
            if(d[v] > d[u] + dist[u][j]){
                d[v] = d[u] + dist[u][j];
                prev[v] = u;
            }
        }
    };
    for(i = 0; i < n; i++){ cout << i << " " << d[i] << endl; }
    for(i = 0; i < n; i++){
        delete adj[i]; delete dist[i]; }
    delete d;
    delete prev;
    delete Q;
    cin >> n;
 
    return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<vector>
#define MAX 101
#define INF 100001
using namespace std;

int n, isSelected[MAX], dist[MAX];
vector<pair<int, int>> ver[MAX];

void initDijkstra(void);
void dijkstra(void);
bool doesFinished(void);

int main() {
	int i, j, id, k, v, c;
	cin >> n;
	for (i = 0; i < n; i++) {
		cin >> id >> k;
		for (j = 0; j < k; j++) {
			cin >> v >> c;
			ver[id].push_back(make_pair(v, c));
		}
	}

	initDijkstra();

	while (!doesFinished())dijkstra();

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

	return 0;
}

void initDijkstra(void) {

	dist[0] = 0;
	isSelected[0] = 1;
	for (int i = 1; i <= n; i++)dist[i] = INF;

	vector<pair<int, int>>::iterator itv;

	for (itv = ver[0].begin(); itv != ver[0].end(); itv++) {
		dist[itv->first] = itv->second;
	}

}

void dijkstra(void) {
	int i, minu, mindist = INF;
	vector<pair<int, int>>::iterator itv;

	for (i = 0; i < n; i++) {
		if (isSelected[i] == 0)continue;
		for (itv = ver[i].begin(); itv != ver[i].end(); itv++){
			if (isSelected[itv->first] == 1)continue;
			if (itv->second < mindist) {
				mindist = itv->second;
				minu = itv->first;
			}
		}
	}
	isSelected[minu] = 1;
	//dist[minu] = dist[minp] + mindist;
	for (itv = ver[minu].begin(); itv != ver[minu].end(); itv++) {
		if (isSelected[itv->first] == 1)continue;
		dist[itv->first] = min(dist[minu] + itv->second, dist[itv->first]);
	}
}

bool doesFinished(void) {
	for (int i = 0; i < n; i++) {
		if (isSelected[i] == 0)return false;
	}
	return true;
}

C++: #include <iostream>
#include <algorithm>
#include <cmath>
#include <cstdio>
using namespace std;
#define MAX 10000000

int b[110];

int solve(int a[110][110], int n){
	b[0] = 0;
	for(int i = 0;i < n;i++){
		for(int j = 1;j < n;j++){
			//if(j == 4)cout << b[4] << i << " " << endl;
			if(a[i][j] != -1)b[j] = min(b[j], a[i][j]+b[i]);
			//if(j == 4)cout << b[4] << i << " " << endl;
		}
	}
	//cout << endl;
	return 0;
}

int main(){
	int a[110][110], n;
	fill((int*)a, (int*)(a+110), -1);
	fill(b, b+110, MAX);
	cin >> n;
	for(int i = 0;i < n;i++){
		int u, k, c, d;
		cin >> u >> k;
		for(int j = 0;j < k;j++){
			cin >> c >> d;
			a[u][c] = a[c][u] = d;
		}
	}
	for(int i = 0;i < n;i++)solve(a, n);
	for(int i = 0;i < n;i++){
		cout << i << " " << b[i] << endl;
	}
	
	return 0;
}
/*
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
*/