Go: package main

import (
	"bufio"
	"fmt"
	"io"
	"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() {
	doMain(os.Stdin)
}

func doMain(reader io.Reader) {
	sc := bufio.NewScanner(reader)
	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{0}, shortestList, adjacentMatrix)
	for _, v := range shortestList {
		fmt.Println(v.getEnd(), v.shortest)
	}
}

func (si ShortestInfo) getEnd() int {
	if len(si.edges) == 0 {
		return 0
	} 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]
}

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] = shortestInfo
}

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

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

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

#define rep(i, a, b) for (int i = (a); i < (int)(b); i++)
#define rrep(i, a, b) for (int i = (a); i >= (int)(b); i--)
#define all(x) (x).begin(), (x).end()
using i32 = int32_t;
using i64 = int64_t;
using f32 = float;
using f64 = double;
using P   = pair<int, int>;

template <class T>
bool chmin(T& a, T b) {
    if (a > b) {
        a = b;
        return true;
    } else {
        return false;
    }
}
template <class T>
bool chmax(T& a, T b) {
    if (a < b) {
        a = b;
        return true;
    } else {
        return false;
    }
}

template <class T>
void dump_vec(const vector<T>& v) {
    auto len = v.size();
    rep(i, 0, len) {
        cout << v[i] << (i == (int)len - 1 ? "\n" : " ");
    }
}

struct FastIO {
    FastIO() {
        cin.tie(0);
        ios::sync_with_stdio(false);
        cout << fixed << setprecision(20);
    }
} FASTIO;

//---------------------------------------------------------------------------------------------------

struct Edge {
    int from, to;
    i64 cost;
    Edge() {}
    Edge(int t, i64 c) : from(-1), to(t), cost(c) {}
    Edge(int f, int t, i64 c) : from(f), to(t), cost(c) {}

    bool operator<(const Edge& r) const {
        return cost < r.cost;
    }
    bool operator>(const Edge& r) const {
        return cost > r.cost;
    }
};

using Vertex = vector<Edge>;
using Graph  = vector<Vertex>;

// 無向
void link(Graph& g, int from, int to, int cost = 1) {
    g[from].push_back(Edge(from, to, cost));
    g[to].push_back(Edge(to, from, cost));
    return;
}

// 有向
void connect(Graph& g, int from, int to, int cost = 1) {
    g[from].push_back(Edge(from, to, cost));
    return;
}

vector<i64> dijkstra(const Graph& g, int start) {
    const auto inf = numeric_limits<i64>::max();
    vector<i64> dist(g.size(), inf);

    using Pi = pair<i64, int>;
    priority_queue<Pi, vector<Pi>, greater<Pi>> que;
    dist[start] = 0;
    que.push(make_pair(0, 0));
    while (!que.empty()) {
        const auto e    = que.top();
        const auto cost = e.first;
        const auto from = e.second;
        que.pop();
        if (dist[from] < cost) continue;

        for (const auto& e : g[from]) {
            const auto next_cost = e.cost + cost;
            if (chmin(dist[e.to], next_cost)) {
                que.push(make_pair(next_cost, e.to));
            }
        }
    }

    return dist;
}

//---------------------------------------------------------------------------------------------------

signed main() {
    int N;
    cin >> N;
    Graph G(N);
    rep(i, 0, N) {
        int u, k;
        cin >> u >> k;
        rep(j, 0, k) {
            int v, c;
            cin >> v >> c;
            connect(G, u, v, c);
        }
    }
    auto dist = dijkstra(G, 0);
    rep(i, 0, N) {
        cout << i << " " << dist[i] << "\n";
    }
}

C++: #include <bits/stdc++.h>

using namespace std;

#define llong long long 
typedef pair<long int, int> P;
long int d[10001];
bool Dec[10001];
vector<P> edges[10001];
priority_queue<P, vector<P>, greater<P> > q;

void solve(){
	fill_n(d, 10001, 9999999);
	d[0] = 0;
	fill_n(Dec, 10001, false);
	q.push(P(0,0));

	while(!q.empty()){
		P p = q.top(); q.pop();
		if(Dec[p.second] == true) continue;
		Dec[p.second] = true;
		d[p.second] = p.first;

		for(int i = 0; i < edges[p.second].size(); i++){
			P e = edges[p.second][i];
			if(d[e.second] > p.first + e.first){
				q.push(P(p.first + e.first, e.second));
			}
		}
	}

	return;
}

int main(){
	int N;
	cin >> N;
	for(int i = 0; i < N; i++){
		int num;
		int howedge;
		cin >> num >> howedge;
		for(int j = 0; j < howedge; j++){
			int to;
			long int cost;
			cin >> to >> cost;
			edges[num].push_back(P(cost, to));
		}
	}

	solve();

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

	return 0;
}