Go: package main

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

const (
	MAX_N      = 100
	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 <stdio.h>
#include <vector>
#include <list>
#include <map>
#include <array>
#include <memory>
#include <string>
#include <iostream>
#include <sstream>
#include <algorithm>
#include <cmath>
#include <unordered_map>
#include <stdexcept>
#include <numeric>
#include <queue>

using std::string;
using std::vector;


//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// util
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

std::vector<std::string> split(const std::string& input, char delimiter)
{
    std::istringstream stream(input);

    std::string field;
    std::vector<std::string> result;
    while (std::getline(stream, field, delimiter)) {
        result.push_back(field);
    }
    return result;
}



//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// user func
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

void printList(const vector<int>& list) {
    // print
    for(int i = 0; i < list.size(); i++){
        printf("%d", list[i]);
        if ( i + 1 != list.size() ) {
            printf(" ");
        }
    }
    printf("\n");
}



//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// logic
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

static int MAX = 1000000;

class Node{
public:
    Node(int id, int numEdge)
     : id(id)
     , edges(vector<int>(numEdge, MAX))
    {
        // constructer
    }
    
    void Edge(int id, int weight){
        this->edges[id] = weight;
    }

    vector<int> Edges() {
        return this->edges;
    }

    int id;
    bool done = false;
    vector<int> edges;
};

class List{
public:
    // constructer
    List(int numNode)
        : results(numNode)
    {
        for (int i = 0; i < numNode; i++) {
            this->nodes.push_back(Node(i, numNode));
            this->results[i] = MAX;
        }
    }

    void SetWeight(int from, int to, int weight)
    {
        this->nodes[from].Edge(to, weight);
    }
    
    vector<int> ShortedPath() {
        // this->Enqueue(0);
        this->results[0] = 0;
        this->queue.push(0);
        this->Traverse();
        return this->results;
    }

    void Traverse() {
        while(!this->queue.empty()) {
            int queueIndex = queue.front();
            queue.pop();
            vector<int> edges = this->nodes[queueIndex].Edges();
            for (int i = 0; i < edges.size(); i++) {
                // update result
                int myWeight = this->results[queueIndex];
                this->results[i] = std::min(this->results[i], myWeight + edges[i]);
            }
            // printList(this->results);
            // enqueue
            this->Enqueue(queueIndex);
            // done flag
            this->nodes[queueIndex].done = true;
        }
    }

    void Enqueue(int index) {
        // copy weights
        if (this->nodes[index].done) return;
        std::list<std::pair<int, int>> weights;
        for (int i = 0; i <  this->nodes[index].Edges().size(); i++) {
            weights.push_back(std::make_pair(i, this->nodes[index].Edges()[i]));
        }
        // sort
        weights.sort([](auto& lhs, auto& rhs){
            return lhs.second < rhs.second;
        });
        // enqueue
        for (auto weight : weights){
            queue.push(weight.first);
        }
    }
    
    

    void Print() {
        for (int i = 0; i < this->nodes.size(); i++) {
            printf("%d: ", i);
            for (int j = 0; j < this->nodes[i].Edges().size(); j++) {
                printf("%d (%d) ", j, this->nodes[i].Edges()[j]);
            }
            printf("\n");
        }
    }
private:
    std::queue<int> queue;
    std::vector<int> results;
    vector<Node> nodes;
};

void solve() {

    int n;
    scanf("%d", &n);
    List list(n);

    for (int i = 0; i < n; i++){
        int key;
        scanf("%d", &key);
        int k;
        scanf("%d", &k);
        for (int j = 0; j < k; j++) {
            int dest;
            int weight;
            scanf("%d %d", &dest, &weight);
            list.SetWeight(key, dest, weight);
        }
    }
    // list.Print();
    auto result = list.ShortedPath();
    for(int i = 0; i < result.size(); i++) {
        printf("%d %d\n", i, result[i]);
    }
}

void test(){

}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// main
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
int main() {
    solve();
    // test();
    return 0;
}