Go: package main

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

const BIG_COST = 200000

type Path struct {
	node int
	cost int
}

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

	nNodes := scanInt(sc)

	// 各頂点につながる頂点一覧を得るための隣接リスト
	graph := make([][]Path, nNodes)

	for i := 0; i < nNodes; i++ {
		u := scanInt(sc)
		k := scanInt(sc)
		graph[i] = make([]Path, k)
		for d := 0; d < k; d++ {
			graph[u][d] = Path{
				node: scanInt(sc),
				cost: scanInt(sc),
			}
		}
	}

	// 0 から各頂点への最小コストを保存する配列
	minCosts := make([]int, nNodes)

	minCosts[0] = 0
	for i := 1; i < nNodes; i++ {
		minCosts[i] = BIG_COST
	}

	// 各頂点が調査済みかどうかを保持する配列
	checked := make([]bool, nNodes)

	// 最小コストのパスを高速に取得するためのヒープ。
	// コストが小さいものほどルートに来るようにする。
	heap := NewHeap(func(a, b Path) bool {
		return a.cost < b.cost
	})

	heap.insert(Path{node: 0, cost: 0})
	for heap.size > 0 {
		u := heap.extractMax()

		// 隣接行列を使っていた時とは違い、ヒープには
		// 同じノードへのパスが複数含まれうる。そのため既によりコストの低い
		// パスが見つかっている場合は無視する。
		if minCosts[u.node] < u.cost {
			continue
		}

		checked[u.node] = true

		for _, v := range graph[u.node] {
			cost := v.cost + u.cost
			if !checked[v.node] && cost < minCosts[v.node] {
				minCosts[v.node] = cost
				heap.insert(Path{node: v.node, cost: cost})
			}
		}
	}

	w := bufio.NewWriter(os.Stdout)
	for i, cost := range minCosts {
		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
}

// --- From ALDS1_9_C: Priority Queue

type Heap struct {
	size   int
	heap   []Path
	isHigh func(a, b Path) bool
}

func NewHeap(isHigh func(a, b Path) bool) Heap {
	heap := make([]Path, 1) // 先頭は不使用
	return Heap{size: 0, heap: heap, isHigh: isHigh}
}

func (h *Heap) insert(v Path) {
	h.size += 1
	if h.size > len(h.heap)-1 {
		h.heap = append(h.heap, v)
	} else {
		h.heap[h.size] = v
	}

	for i := h.size; i > 1; {
		parent := i / 2
		if h.isHigh(h.heap[parent], h.heap[i]) {
			break
		}
		h.heap[i], h.heap[parent] = h.heap[parent], h.heap[i]
		i = parent
	}
}

func (h *Heap) extractMax() Path {
	if h.size <= 0 {
		panic("cannot extract from empty heap")
	}

	max := h.heap[1]
	h.heap[1] = h.heap[h.size]
	h.size -= 1
	h.maxHeapify(1)

	return max
}

func (h *Heap) maxHeapify(idx int) {
	left := idx * 2
	right := left + 1
	largest := idx

	if left <= h.size {
		if h.isHigh(h.heap[left], h.heap[idx]) {
			largest = left
		}
		if right <= h.size && h.isHigh(h.heap[right], h.heap[largest]) {
			largest = right
		}
	}

	if largest != idx {
		h.heap[idx], h.heap[largest] = h.heap[largest], h.heap[idx]
		h.maxHeapify(largest)
	}
}

C++: #include <bits/stdc++.h>
using namespace std;
#define MAX 10005
#define INFTY INT_MAX

struct Node {
    int point;
    int weight;
    Node() {}
    Node(int p, int w) {
        point = p;
        weight = w;
    }
};

bool operator<(Node left, Node right) {
    return (left.weight > right.weight);
}

vector<vector<Node> > vec(MAX);
vector<Node> ve;
priority_queue<Node> pq;
Node node;
int n;

void dijkstra() {
    int d[MAX], color[MAX];
    for (int i = 0; i < n; i++) {
        d[i] = INFTY;
        color[i] = 0;
    }
    d[0] = 0;
    pq.push(Node(0, d[0]));
    while (!pq.empty()) {
        node = pq.top();
        pq.pop();
        int u = node.point;
        color[u] = 1;
        if (d[u] < node.weight)
            continue;
        for (int i = 0; i < vec[u].size(); i++) {
            int v = vec[u][i].point;
            int c = vec[u][i].weight;
            if (d[u] + c < d[v]) {
                d[v] = d[u] + c;
                pq.push(Node(v, d[v]));
            }
        }
    }
    for (int i = 0; i < n; i++) {
        cout << i << " " << d[i] << endl;
    }
}

int main(void) {
    cin >> n;
    int u, k;
    for (int i = 0; i < n; i++) {
        ve.clear();
        cin >> u >> k;
        while (k--) {
            cin >> node.point >> node.weight;
            ve.push_back(node);
        }
        vec[u] = ve;
    }

    dijkstra();
}

C++: #include <iostream>
#include <iomanip>
#include <vector>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <algorithm>
#include <cstdio>
#include <utility>
#include <string>
#include <cmath>
#include <cstdlib>
#include <cstring>

using namespace std;

typedef uint64_t u64;
typedef int64_t s64;
typedef uint32_t u32;
typedef int32_t s32;
typedef vector<s32> vs32;
typedef vector<u32> vu32;
typedef vector<s64> vs64;
typedef vector<u64> vu64;

const double PI=3.14159265358979323846;

#define MAX(x, y) ((x) < (y) ? (y) : (x))
#define MIN(x, y) ((x) > (y) ? (y) : (x))

#define rep(i, N) for(int i = 0; i < N; ++i)

#define CEIL(x, y) (((x) + (y) - 1) / (y))
#define MOD 1000000007ULL

class Graph
{
public:
    enum
    {
        WHITE = 0,
        GRAY = 1,
        BLACK = 2,
    };

    Graph() {}
    Graph(int n)
    : color(n, WHITE), M(n), d(n, INFTY)
    {}
    ~Graph() {}

    void dijkstra(int s)
    {
        d[s] = 0;
        priority_queue< pair<int, int> > pq;

        pq.push(make_pair(0, s));
        while (!pq.empty())
        {
            pair<int, int> du = pq.top(); pq.pop(); 

            int u = du.second;
            int minv = -du.first;

            color[u] = BLACK;

            if (d[u] < -minv) continue;

            for (auto dv : M[u])
            {
                int v = dv.first;
                int w = dv.second;
                if (color[v] != BLACK && d[v] > d[u] + w)
                {
                    d[v] = d[u] + w;
                    color[v] = GRAY;
                    pq.push(make_pair(-d[v], v));
                }
            }
        }
    }

    static const int INFTY = 1e9;
    vs32 color;
    vector< vector< pair<int, int> > > M;
    vs32 d;
};

int main()
{
    cin.tie(0);
    ios::sync_with_stdio(false);

    int n;
    cin >> n;

    Graph g(n);

    int u, v;
    int w;
    int c;
    rep (i, n)
    {
        cin >> u >> c;
        rep (j, c)
        {
            cin >> v >> w;
            g.M[u].emplace_back(v, w);
        }
    }

    g.dijkstra(0);
    rep (i, n)
    {
        cout << i << " " << g.d[i] << "\n";
    }
    return 0;
}

C++: #include <iostream>
#include <algorithm>
#include <queue>
using namespace std;
static const int MAX = 10000;
static const int INFTY = (1<<21);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n;
vector<pair<int, int> > adj[MAX];

void dijkstra();


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

    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(make_pair(v, c));
        }
    }

    dijkstra();

}



void dijkstra() {
    priority_queue<pair<int, int> > PQ;
    int color[MAX];
    int d[MAX];
    for ( int i = 0; i < n; i++) {
        d[i] = INFTY;
        color[i] = WHITE;
    }

    d[0]  = 0;
    PQ.push(make_pair(0, 0));
    color[0] = GRAY;

    while ( !PQ.empty()) {
        pair<int, int> f = PQ.top(); PQ.pop();
        int u = f.second;

        color[u] = BLACK;

        // take the minimum value, ignore if it is not the shortest
        if ( d[u] < f.first * (-1) ) continue;

        for ( int j = 0; j < adj[u].size(); j++ ) {
            int v = adj[u][j].first;
            if (color[v] == BLACK) continue;
            if ( d[v] > d[u] + adj[u][j].second) {
                d[v] = d[u] + adj[u][j].second;
                // multiple (-1) because of priority large value in priority_queue
                PQ.push(make_pair(d[v] * (-1), v));
                color[v] = GRAY;
                }
        }
    }

    for ( int i = 0; i < n; i++ ) {
        cout << i << " " << ( d[i] == INFTY ? -1 : d[i] ) << '\n';
    }
}