Go: package main

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

var scanner = bufio.NewScanner(os.Stdin)

func nextString() string {
	scanner.Scan()
	return scanner.Text()
}

func nextInt() int {
	n, err := strconv.Atoi(nextString())
	if err != nil {
		fmt.Printf("strconv.Atoi failed: %v\n", err)
	}
	return n
}

var infty = 1000000000

type DirectedGraphNodeID int

type DirectedGraphNode struct {
	key         DirectedGraphNodeID
	adjacents   []*DirectedGraphNode
	costs       []int
	distance    int
	predecessor *DirectedGraphNode
}

func newDirectedGraph(nNodes int) *DirectedGraph {
	graph := DirectedGraph{}
	graph.nodes = make([]*DirectedGraphNode, nNodes)
	for i := 0; i < nNodes; i++ {
		node := DirectedGraphNode{}
		node.key = DirectedGraphNodeID(i)
		node.distance = infty
		graph.nodes[i] = &node
	}
	return &graph
}

type DirectedGraph struct {
	nodes []*DirectedGraphNode
}

func (g *DirectedGraph) setAdjacency(i, j DirectedGraphNodeID, cost int) {
	g.nodes[i].adjacents = append(g.nodes[i].adjacents, g.nodes[j])
	g.nodes[i].costs = append(g.nodes[i].costs, cost)
}

func (g *DirectedGraph) print() {
	for i := 0; i < len(g.nodes); i++ {
		node := g.nodes[i]
		key := node.key
		strings := []string{strconv.Itoa(int(key)), strconv.Itoa(node.distance)}
		for j := 0; j < len(node.adjacents); j++ {
			nodeJ := fmt.Sprintf("(%v, %v)", node.adjacents[j].key, node.costs[j])
			strings = append(strings, nodeJ)
		}
		fmt.Printf("%v\n", strings)
	}
}

func (g *DirectedGraph) relaxEdge(l, r *DirectedGraphNode, w int) {
	if r.distance > l.distance+w {
		// fmt.Printf("%v -> %v, %v\n", l.key, r.key, l.distance+w)
		r.distance = l.distance + w
		r.predecessor = l
	}
}

func main() {
	scanner.Split(bufio.ScanWords)

	nNodes := nextInt()
	graph := newDirectedGraph(nNodes)

	for i := 0; i < nNodes; i++ {
		iNode := DirectedGraphNodeID(nextInt())
		nAdjacent := nextInt()
		for j := 0; j < nAdjacent; j++ {
			jNode := DirectedGraphNodeID(nextInt())
			cost := nextInt()
			graph.setAdjacency(iNode, jNode, cost)
		}
	}

	graph.nodes[0].distance = 0
	for iNode := 0; iNode < nNodes; iNode++ {
		for iLeft := 0; iLeft < len(graph.nodes); iLeft++ {
			nodeLeft := graph.nodes[iLeft]
			for iRight := 0; iRight < len(nodeLeft.adjacents); iRight++ {
				nodeRight := nodeLeft.adjacents[iRight]
				cost := nodeLeft.costs[iRight]
				graph.relaxEdge(nodeLeft, nodeRight, cost)
			}
		}
	}

	// graph.print()

	for iNode := 0; iNode < len(graph.nodes); iNode++ {
		node := graph.nodes[iNode]
		fmt.Println(node.key, node.distance)
	}
}

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

using namespace std;

int main() {

	int INF = 10000000;

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

	vector<pair<int, int>> G[n];
	for (int i = 0; i < n; ++i) {
		int from;
		scanf("%d", &from);

		int v;
		scanf("%d", &v);

		for (int j = 0; j < v; ++j) {
			int to;
			int w;
			scanf("%d %d", &to, &w);
			G[from].push_back(make_pair(to, w));
		}
	}

	int C[n];
	for (int i = 0; i < n; ++i)
		C[i] = INF;

	int color[n];
	int WHITE = 0;
	int BLACK = 1;
	for (int i = 0; i < n; ++i)
		color[i] = WHITE;

	priority_queue<pair<int, int>> PQ;
	PQ.push(make_pair(0, 0));
	C[0] = 0;
	while (!PQ.empty()) {
		int u = PQ.top().second;
		PQ.pop();
		color[u] = BLACK;
		for (int i = 0; i < (int) G[u].size(); ++i) {
			auto c = G[u][i];
			if (color[c.first] != BLACK && c.second + C[u] < C[c.first]) {
				C[c.first] = c.second + C[u];
				PQ.push(make_pair(C[c.first] * -1, c.first));
			}
		}
	}

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

	return 0;
}

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

int main() {
    int n;
    cin >> n;

    int a[n][n];
    int done[n]; // -1: まだ ソレ以外: 確定距離
    for (int i = 0; i < n; ++i) {
        done[i] = -1;
        for (int j = 0; j < n; ++j) {
            a[i][j] = -1;
        }
    }
    for (int i = 0; i < n; ++i) {
        int u, k;
        cin >> u >> k;
        for (int j = 0; j < k; ++j) {
            int v, c;
            cin >> v >> c;
            a[i][v] = c;
        }
    }

    // デバッグ用
//     for (int i = 0; i < n; ++i) {
//         for (int j = 0; j < n; ++j) {
//             cout << i << " " << j << " " << a[i][j] << endl;
//         }
//     }

    // 最初は0が確定済みのノードとなる
    done[0] = 0;

    // 確定済みのノードから行ける、未到達の最小のノードを探す
    // その最小のノードは次の確定済みとする...
    // とりあえずデバッグがてら10回す (最終的にwhileにして条件で対応する)
    // 全てdoneになったら終了
    for (int r = 0; r < n-1; ++r) {
        int next_node = -1;
        int next_cost = 1000000;
        for (int i = 0; i < n; ++i) {
            if (done[i] == -1) {
                // 未確定であれば何もしない
                continue;
            }

            for (int j = 0; j < n; ++j) {
                // 到達済みは見ない
                if (done[j] != -1) {
                    continue;
                }

                // コストが-1なら到達できない
                if (a[i][j] == -1) {
                    continue;
                }

                // 行けるところのコスト (iまでの距離+そこからの距離) を探す
//                cout << "src:" << i << " dst:" << j << " cost:" << a[i][j] << " total:" << done[i] + a[i][j] << endl;

                // 今のnext_costよりもtotalcostが小さければ、次のノードにしたい
                if ((done[i] + a[i][j]) < next_cost) {
                    next_cost = done[i] + a[i][j];
                    next_node = j;
                }
            }
        }
//        cout << "iter:" << r << endl;
//        cout << "next_node:" << next_node << endl;
//        cout << "next_cost:" << next_cost << endl;
        done[next_node] = next_cost;
    }

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

    return 0;
}

C++: #include<stdio.h>
#define MAX 100
#define INFTY (2<<21)
#define WHITE 0
#define GRAY 1
#define BLACK 2

int M[MAX][MAX];
int d[MAX];
int color[MAX];

void dijkstra(int n) {
    int u, mincost;
    d[0] = 0;
    color[0] = GRAY;

    while (true) {
        mincost = INFTY;
        u = -1;

        for (int i=0; i<n; i++) {
            if (color[i]!=BLACK && d[i]<mincost) {
                u = i;
                mincost = d[i];
            }
        }

        if (u==-1) break;
        color[u] = BLACK;

        for (int i=0; i<n; i++) {
            if (color[i]!=BLACK && M[u][i]<INFTY) {
                color[i] = GRAY;
                if (d[u]+M[u][i]<d[i]) {
                    d[i] = d[u] + M[u][i];
                }
            }
        }
    }
}

int main() {
    int n, k, v, c, u;
    scanf("%d", &n);

    for (int i=0; i<n; i++) {
        d[i] = INFTY;
        color[i] = WHITE;
        for (int j=0; j<n; j++) {
            M[i][j] = INFTY;
        }
    }

    for (int i=0; i<n; i++) {
        scanf("%d %d", &u, &k);
        for (int j=0; j<k; j++) {
            scanf("%d %d", &v, &c);
            M[u][v] = c;
        }
    }

    dijkstra(n);

    for (int i=0; i<n; i++) {
        printf("%d %d\n", i, d[i]);
    }

    return 0;
}

C++: #include<iostream>
#include<vector>
using namespace std;
int map[100][100];
int n;
int d[100];
int color[100];
int INF = 1000000;
void solve() {
	int all = 1;
	d[0] = 0;
	color[0] = 1;
	vector<int>v;
	v.push_back(0);
	while (all != n)
	{
		int min = INF;
		int k;
		for (int i = 0; i < v.size(); i++) {
			for (int j = 0; j < n; j++) {
				if (!color[j] && d[v[i]] + map[v[i]][j] <= d[j]) {
					d[j] = d[v[i]] + map[v[i]][j];
					if (d[j] < min) {
						min = d[j];
						k = j;
					}
				}
			}
		}
		color[k] = 1;
		v.push_back(k);
		all++;
	}
}
int main(void) {
	cin >> n;
	for (int i = 0; i < n; i++) {
		d[i] = INF;
		for (int j = 0; j < n; j++) map[i][j] = INF;
	}
	for (int i = 0; i < n; i++) {
		int k,all;
		cin >> k>>all;
		for (int j = 0; j < all; j++) {
			int a, b;
			cin >> a >> b;
			map[k][a] = b;
		}
	}
	solve();
	for (int i = 0; i < n; i++) {
		cout << i<<" "<<d[i]<<endl;
	}
}