Go: package main

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

const (
	MAX_N      = 10000
	MAX_WEIGHT = 100000
)

type Edge struct {
	start  int
	end    int
	weight int
}

type ShortestInfo struct {
	edges    []Edge
	shortest int
}

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

	n, err := nextInt(sc)
	if err != nil {
		panic(err)
	}

	shortestList := make([]ShortestInfo, n)
	for i := 1; i < n; i++ {
		shortestList[i] = ShortestInfo{edges: []Edge{}, shortest: MAX_N*MAX_WEIGHT + 1}
	}

	adjacentMatrix, err := createAdjacentMatrix(n, sc)
	if err != nil {
		panic(err)
	}

	sssp([]int{1}, shortestList, adjacentMatrix)
	for _, v := range shortestList {
		fmt.Printf("%d %d\n", v.getEnd()-1, v.shortest)
	}
}

func (si ShortestInfo) getEnd() int {
	if len(si.edges) == 0 {
		return 1
	} else {
		return si.edges[len(si.edges)-1].end
	}
}

func createAdjacentMatrix(n int, sc *bufio.Scanner) ([][]int, error) {
	adjacentMatrix := make([][]int, n)
	for i := 0; i < n; i++ {
		id, err := nextInt(sc)
		if err != nil {
			return nil, err
		}
		adjacentMatrix[id] = make([]int, n)
		for j := 0; j < n; j++ {
			adjacentMatrix[id][j] = -1
		}
		vertexNum, err := nextInt(sc)
		if err != nil {
			return nil, err
		}
		for j := 0; j < vertexNum; j++ {
			v, err := nextInt(sc)
			if err != nil {
				return nil, err
			}
			c, err := nextInt(sc)
			if err != nil {
				return nil, err
			}
			adjacentMatrix[id][v] = c
		}
	}
	return adjacentMatrix, nil
}

func sssp(nodeStack []int, shortestList []ShortestInfo, adjacentMatrix [][]int) {
	for len(nodeStack) > 0 {
		currentNode := nodeStack[0]
		nodeStack = nodeStack[1:]
		currentShortest := getShortest(currentNode, shortestList)
		adjacents := findAdjacents(currentNode, adjacentMatrix)
		for i := 0; i < len(adjacents); i++ {
			adj := adjacents[i]
			if currentShortest.shortest+adj.weight < getShortest(adj.end, shortestList).shortest {
				setShortest(adj.end, adj, currentShortest, shortestList)
				nodeStack = append(nodeStack, adj.end)
			}
		}
	}
}

func getShortest(node int, shortestList []ShortestInfo) ShortestInfo {
	return shortestList[node-1]
}

func setShortest(node int, edge Edge, currentShortest ShortestInfo, shortestList []ShortestInfo) {
	newEdges := make([]Edge, len(currentShortest.edges)+1)
	for i := 0; i < len(newEdges)-1; i++ {
		newEdges[i] = currentShortest.edges[i]
	}
	newEdges[len(newEdges)-1] = edge
	shortestInfo := ShortestInfo{edges: newEdges, shortest: currentShortest.shortest + edge.weight}
	shortestList[node-1] = shortestInfo
}

func findAdjacents(currentNode int, adjacentMatrix [][]int) []Edge {
	adjacents := adjacentMatrix[currentNode-1]
	edges := []Edge{}
	for i, v := range adjacents {
		if v > 0 {
			edges = append(edges, Edge{start: currentNode, end: i + 1, weight: v})
		}
	}
	return edges
}

func nextInt(sc *bufio.Scanner) (int, error) {
	sc.Scan()
	return strconv.Atoi(sc.Text())
}

C++: #include <iostream>
#include <cstdio>
#include <cstdlib>
#include <stack>
#include <vector>
#include <algorithm>
#include <cmath>
#include <climits>
#include <cstring>
#include <queue>
#include <string>

using namespace std;

const double PI = 3.14159265358979;

//int G[101][101];
int visited[10001];
int n;

int d[10001];


struct Vertex {
	int u;
	int weight;

	friend bool operator < (Vertex a, Vertex b) {
		return a.weight > b.weight;
	}
};

vector<Vertex> G[10001];

void dijkstra(int start) {

	priority_queue<Vertex> PQ;

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

	d[start] = 0;
	PQ.push(Vertex{ 0,0 });

	while (!PQ.empty()) {
		Vertex f = PQ.top();
		PQ.pop();
		int u = f.u;
		if (visited[u]) {
			continue;
		}
		else {
			visited[u] = 1;
		}

		//if (f.weight > d[u]) continue;

		
		for (int j = 0; j < G[u].size(); j++)
		{
			int v = G[u][j].u;
			if (!visited[v]) {
				if (d[u] + G[u][j].weight < d[v]) {
					PQ.push(Vertex{ v, d[u] + G[u][j].weight });
					d[v] = d[u] + G[u][j].weight;
				}
			}
		}
	}


}

int main() {
	
	
	cin >> n;

	for (int i = 0; i < n; i++)	{
		int u, k; cin >> u >> k;
		for (int j = 0; j < k; j++)	{
			int v, w; cin >> v >> w;
			G[u].push_back(Vertex{ v, w });
		}
	}

	dijkstra(0);

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

	return 0;
}

C++: #include <iostream>
#include <queue>
#include <utility>
#include <vector>

#define MAX_NODE 10000
#define INF 1000000000

using namespace std;

struct Edge {
	int to, w;
};

typedef pair<int, int> P;

vector<Edge> adj[MAX_NODE];
int d[MAX_NODE];

void dijkstra(int n, int start) {
	priority_queue<P, vector<P>, greater<P> > heap;
	fill(d, d + n, INF);
	d[start] = 0;
	heap.push({0, start});

	while (!heap.empty()) {
 		P p = heap.top();
 		heap.pop();
 		int from = p.second;
 		if (d[from] < p.first)
 			continue;
 		for (int i = 0; i < adj[from].size(); i++) {
 			Edge e = adj[from][i];
	 		if (d[from] + e.w < d[e.to]) {
	 			d[e.to] = d[from] + e.w;
	 			heap.push( {d[e.to], e.to} );
	 		}
	 	}
	}
}

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

C++: #include <iostream>
#include <vector>
using namespace std;
int n;
/*
int dat[100][100];
int cost[100];
int done[100];

void prim(){
	for(int i=0;i<n;i++){
		cost[i]=1<<21;
		done[i]=0;
	}
	int s=0;	
	int next, ncost=1<<21;
	done[s]=1;
	cost[s]=0;
	while(1){
		ncost=1<<21;
		for(int j=0;j<n;j++){
			if(done[j]){
				for(int i=0;i<n;i++){
					if(dat[j][i]!=-1){
						if(cost[i]>=dat[j][i]&&!done[i]){
							cost[i]=dat[j][i];
						}
						if(ncost>cost[i]&&!done[i]){
							next=i;
							ncost=cost[i];
						}
					}
				}
			}
		}
//		cout<<"next:"<<next<<" cost:"<<cost[next]<<endl;
		done[next]=1;
		int flag=true;
		for(int i=0;i<n;i++){
			if(!done[i]) flag = false;
		}
		if(flag)
			return;
	}
}


void dijk(){
	for(int i=0;i<n;i++){
		cost[i]=1<<21;
		done[i]=0;
	}
	int s=0;	
	int next, ncost=1<<21;
	done[s]=1;
	cost[s]=0;
	while(1){
		ncost=1<<21;
		for(int j=0;j<n;j++){
			if(done[j]){
				for(int i=0;i<n;i++){
					if(dat[j][i]!=0){
						if(cost[i]>=dat[j][i]+cost[j]){
							cost[i]=dat[j][i]+cost[j];
						}
						if(ncost>cost[i]&&!done[i]){
							next=i;
							ncost=cost[i];
						}
					}
				}
			}
		}
//		cout<<"next:"<<next<<" cost:"<<cost[next]<<endl;
		done[next]=1;
		int flag=true;
		for(int i=0;i<n;i++){
			if(!done[i]) flag = false;
		}
		if(flag)
			return;
	}
}
*/

vector<vector<int> > dat;
int cost[10000];
int done[10000];

void dijk2(){
	for(int i=0;i<n;i++){
		cost[i]=1<<21;
		done[i]=0;
	}
	int s=0;	
	int next, ncost=1<<21;
	done[s]=1;
	cost[s]=0;
	while(1){
		top:
		ncost=1<<21;
		for(int j=0;j<n;j++){
			if(done[j]){
				for(int i=0;i<n;i++){
					if(dat[j][i]!=0){
						if(!done[i]){
							if(cost[i]>=dat[j][i]+cost[j]){
								cost[i]=dat[j][i]+cost[j];
							}
							if(ncost>cost[i]){
								next=i;
								ncost=cost[i];
							}
						}
					}
				}
			}
		}
//		cout<<"next:"<<next<<" cost:"<<cost[next]<<endl;
		done[next]=1;
		for(int i=0;i<n;i++){
			if(!done[i]) goto top;
		}
		return;
	}
}



int main(){
	int num, from, dist, c;
	cin>>n;	
	dat.reserve(n);
	for(int i=0;i<n;i++){
		vector<int> d(n);
		dat.push_back(d);
	}
	for(int i=0;i<n;i++){
		cin>>from>>num;
		for(int j=0;j<num;j++){
			cin>>dist>>c;
			dat[from][dist]=c;
		}
	}
	dijk2();
	for(int i=0;i<n;i++){
		cout<<i<<" "<<cost[i]<<endl;
	}
	return 0;
}