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 <iostream>
#include <cstdio>
#include <cstring>
#include <stack>
#include <vector>
using namespace std;
const int maxx = 1010;
const int INF = 1 << 30;
int n, m[maxx][maxx];
int u, v ,k, c;
int flag[maxx];

void dijkstra() {
	int d[maxx];
	for (int i = 0; i < n; i++) {
		d[i] = INF;
		flag[i] = 0;
	}

	d[0] = 0;
	while (1) {
		int minv = INF;
		u = -1;
		// ???????????????????°???????
		for (int i = 0; i < n; i++) {
			if (minv > d[i] && flag[i] == 0) {
				u = i;
				minv = d[i];
			}
		}

		if (u == -1)
			break;

		// ?????°???????????\S
		flag[u] = 1;

		// ??´??°?????±u?????????V-S???v?????????????°??????¬
		for (int v = 0; v < n; v++) {
			if (flag[v] == 0 && m[u][v] != INF && d[v] > d[u] + m[u][v]) {
				d[v] = d[u] + m[u][v];
			}
		}
	}

	for (int i = 0; i < n; i++)
		printf("%d %d\n", i, d[i] == INF ? -1 : d[i]);
}
int main()
{
	scanf("%d", &n);
	
	for (int i = 0; i < n; i++) {
		for (int j = 0; j < n; j++) {
			m[i][j] = INF;
		}
	}
	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();
	return 0;
}

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

const int INF=10000002ll;

int n,m[100][100];

void dijkstra();

int main(){
  cin>>n;
  for(int i=0;i<n;i++){
    for(int j=0;j<n;j++){
      m[i][j]=INF;
    }
  }
  
  int k,c,u,v;
  for(int i=0;i<n;i++){
    cin>>u>>k;
    for(int j=0;j<k;j++){
      cin>>v>>c;
      m[u][v]=c;
    }
  }

  dijkstra();

  return(0);
}

void dijkstra(){
  int mn,d[100],sn[100];
  
  for(int i=0;i<n;i++){
    d[i]=INF;
    sn[i]=0;
  }

  d[0]=0;
  while(1){
    mn=INF;
    int u=-1;
    for(int i=0;i<n;i++){
      if(mn>d[i] && sn[i]==0){
	u=i;
	mn=d[i];
      }
    }
    if(u==-1)break;
    sn[u]=1;
    for(int i=0;i<n;i++){
      if(sn[i]==0 && m[u][i]!=INF){
	if(d[i]>d[u]+m[u][i]){
	  d[i]=d[u]+m[u][i];
	}
      }
    }
  }

  int ans;
  for(int i=0;i<n;i++){
    cout<<i<<" ";
    if(d[i]==INF)cout<<"-1"<<endl;
    else cout<<d[i]<<endl;
  }
}

C++: #include <iostream>
#include <vector>
#include <climits>

using namespace std;

int n;
vector<int> g[100];
vector<int> w[100];
int d[100];
char color[100];

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

    for (int j = 0; j < n ; ++j) {
        for (int i = 0; i < n; ++i) {
            for (int k = 0; k < g[i].size(); ++k) {
                int v = g[i][k];
                if(d[i] != INT_MAX && d[v] > d[i] + w[i][k]) {
                    d[v] = d[i] + w[i][k];
                    if(j == n - 1) return true;
                }
            }
        }
    }
    return false;
}

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

    bool neg = bellman();

    for (int j = 0; j < n; ++j) {
        if (d[j] == INT_MAX) cout << "INF" << endl;
        else
            cout << j << " " << d[j] << endl;

    }

    return 0;
}

C++: // -*- mode:c++; coding:utf-8; c-basic-offset:2; -*-
// ALDS1_12_B: Single Source Shortest Path I

#include <algorithm>
#include <cstdio>

using uint = unsigned int;

class Graph {
  const uint n_;
  uint* const g_;
  const uint INFINIT;
  
public:

  Graph(uint n) : n_(n), g_(new uint[(n_*n_)]), INFINIT(100000*(n_-1)+1) {
    std::fill_n(g_, (n_*n_), INFINIT);
  }

  ~Graph() { delete[] g_; }
  
  uint* operator [](uint i) const { return g_+(n_*i); }

  void dijkstra(uint* dist)
  {
    std::fill_n(dist, n_, INFINIT);
    bool visited[n_];
    std::fill_n(visited, n_, false);
    auto i = 0u; // 0-start
    visited[i] = true;
    dist[i] = 0u;
    for (auto n = 0u; n < n_-1; ++n) {
      auto cur_min = INFINIT;
      auto es = (*this)[i];
      auto base_dist = dist[i];
      for (auto j = 0u; j < n_; ++j) {
        if (visited[j]) continue;
        dist[j] = std::min(dist[j], base_dist+es[j]);
        if (cur_min > dist[j]) {
          cur_min = dist[j];
          i = j;
        }
      }
      visited[i] = true;
    }
  }
};

int main()
{
  uint n;
  std::scanf("%u", &n);

  Graph g(n);

  uint u, k, c, v;
  for (auto i = 0u; i < n; ++i) {
    std::scanf("%u %u", &u, &k);
    for (auto j = 0u; j < k; ++j) {
      std::scanf("%u %u", &c, &v);
      g[u][c] = v;
    }
  }

  uint dist[n];
  g.dijkstra(dist);
  for (auto i = 0u; i < n; ++i) {
    std::printf("%u %u\n", i, dist[i]);
  }
}

// eof