Go: package main

import (
	"fmt"
	"bufio"
	"os"
	"strconv"
	"container/heap"
)

type Node struct {
	Id int
	Dis int
}

type PriorityQueue []*Node

func (pq PriorityQueue) Len() int { return len(pq) }

func (pq PriorityQueue) Less(i, j int) bool {
	return pq[i].Dis < pq[j].Dis
}

func (pq PriorityQueue) Swap(i, j int) {
	pq[i], pq[j] = pq[j], pq[i]
}

func (pq *PriorityQueue) Push(x interface{}) {
	*pq = append(*pq, x.(*Node))
}

func (pq *PriorityQueue) Pop() interface{} {
	n := len(*pq)
	pop := (*pq)[n-1]
	*pq = (*pq)[0:n-1]
	return pop
}

func main() {
	var n int
	fmt.Scan(&n)

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

	g := make([][]int, n)
	c := make([][]int, n)
	pq := make(PriorityQueue, 0, n)
	d := make([]int, n)
	for i := 0; i < n; i++ {
		sc.Scan()
		u, _ := strconv.Atoi(sc.Text())
		sc.Scan()
		k, _ := strconv.Atoi(sc.Text())
		g[u] = make([]int, k)
		c[u] = make([]int, k)
		for j := 0; j < k; j++ {
			sc.Scan()
			g[u][j], _ = strconv.Atoi(sc.Text())
			sc.Scan()
			c[u][j], _ = strconv.Atoi(sc.Text())
		}

		if u == 0 {
			d[u] = 0
		} else {
			d[u] = 1 << 30
		}
		pq.Push(&Node{u, d[u]})
	}
	heap.Init(&pq)

	for pq.Len() > 0 {
		node := heap.Pop(&pq).(*Node)
		for i := 0; i < len(g[node.Id]); i++ {
			nextId := g[node.Id][i]
			nextDis := node.Dis + c[node.Id][i]
			if nextDis < d[nextId] {
				d[nextId] = nextDis
				heap.Push(&pq, &Node{nextId, nextDis})
			}
		}
	}

	wr := bufio.NewWriter(os.Stdout)
	for i := 0; i < n; i++ {
		wr.WriteString(strconv.Itoa(i))
		wr.WriteString(" ")
		wr.WriteString(strconv.Itoa(d[i]))
		wr.WriteString("\n")
	}
	wr.Flush()
}

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

using namespace std;
 
vector<int> dijkstra(int s, vector<vector<pair<int, int> > >& G) {
	const int INF = 1e9;
	const int N = G.size();
	vector<int> cost(N, INF);
	priority_queue<pair<int, int>, vector<pair<int, int> >, greater<pair<int, int> > > pq;
	cost[s] = 0;
	pq.push(make_pair(0, s));
	while (!pq.empty()) {
		pair<int, int> p = pq.top(); pq.pop();
		int now = p.second;
		if (cost[now] < p.first) continue;
		for (auto next : G[now]) {
			int nv = next.first, nw = next.second;
			if (cost[nv] > cost[now] + nw) {
				cost[nv] = cost[now] + nw;
				pq.push(make_pair(cost[nv], nv));
			}
		}
	}
	return cost;
}

int main() {
	int n; cin >> n;
	vector<vector<pair<int, int> > > G(n);
	for (int i = 0; i < n; ++i) {
		int u, k; cin >> u >> k;
		while (k--) {
			int v, c; cin >> v >> c;
			G[u].push_back(make_pair(v, c));
		}
	}
	vector<int> ans(dijkstra(0, G));
	for (int i = 0; i < n; ++i)
		cout << i << " " << ans[i] << endl;

	return 0;
}

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

//repetition
#define FOR(i,a,b) for(ll i=(a);i<(b);++i)
#define rep(i, n) for(ll i = 0; i < (ll)(n); i++)

//container util
#define all(x) (x).begin(),(x).end()

//typedef
typedef long long ll;
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<ll> VLL;
typedef vector<VLL> VVLL;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef pair<ll, ll> PLL;

/***********************************************
    Dijkstra はここから O(V^2)
***********************************************/
struct edge{
  ll to, cost;
  edge(ll to, ll cost) : to(to), cost(cost){}
};
/// Dijkstra
///
/// - Parameter from  : 出発点
/// - Parameter to    : 目的点
/// - Parameter v_num : 頂点数
/// - Returns: dist from -> to
vector<ll> dijkstra(int from, int v_num, vector<vector<edge>> & graph){
  ll INF = (ll)1e15;
  vector<ll> d(v_num,INF);        // fromからの距離を格納する
  d[from] = 0;

  priority_queue<PLL,vector<PLL>,greater<PLL>> que;

  que.push(PLL(0,from));
  //頂点はv_num個あるので、v_num周する
  while(!que.empty()){ // もし調べ済みで到達可能な頂点がない場合はbreakする
    PLL  p = que.top();
    que.pop();
    ll node = p.second;
    if(d[node] < p.first) continue;
    for(auto e : graph[node]){
      if(d[e.to] > d[node] + e.cost){
        d[e.to] = d[node] + e.cost;
        que.push(PLL(d[e.to],e.to));
      }
    }
  }

  return d;
}

/***********************************************
    Dijkstra はここまで
***********************************************/
int main(){
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n;
  cin >> n;

  vector<vector<edge>> graph(n);
  rep(i,n){
    int idx,cnt;
    cin >> idx >> cnt;
    rep(j,cnt){
      ll x,cost;
      cin >> x >> cost;
      graph[idx].push_back(edge(x,cost));
    }
  }

  VLL d = dijkstra(0,n,graph);
  rep(i,n){
    cout << i << ' ' << d[i] << endl;
  }
  return 0;
}

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

struct vec {
    int t, c;
    vec(int to, int cost):t(to),c(cost){}
    bool operator>(const vec &r)const{return t>r.t;}
};
vector<vec> adj[100];
int d[100];

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n;
    cin>>n;
    for(int i=0; i<n; i++) d[i]=numeric_limits<int>::max();
    for(int i=0; i<n; i++) {
        int u,k;
        cin>>u>>k;
        adj[u].reserve(k);
        for(int j=0; j<k; j++) {
            int v,c;
            cin>>v>>c;
            adj[u].push_back(vec(v,c));
        }
    }
    priority_queue<vec, vector<vec>, greater<vec> >q;
    q.push(vec(0,0));
    while(!q.empty()) {
        vec e=q.top();
        q.pop();
        if(d[e.t]<=e.c) continue;
        d[e.t]=e.c;
        for(vector<vec>::iterator it=adj[e.t].begin(); it!=adj[e.t].end(); ++it) q.push(vec(it->t, e.c+it->c));
    }
    for(int i=0; i<n; i++) cout<<i<<' '<<d[i]<<'\n';
    return 0;
}

C++: #include <iostream>
#include <set>
#include <vector>
#include <queue>
#include <stack>
#include <utility>
#include <algorithm>

using namespace std;

typedef long long signed int ll;

constexpr ll NIL = -20000000000;

class path{
public:
    int from;
    int to;
    int dist;
    path(){
        from = -1;
        to = -1;
        dist = -1;
    }
    path(int from_,int to_,int dist_){
        from = from_;
        to = to_;
        dist = dist_;
    }
    static bool compare(const path& a,const path& b) {
        return a.from < b.from;
    }
    bool operator<(const path& e) const {
        return this->dist < e.dist;
    }
};

int n,u,k,v,c;
vector<path> w;
ll d[10000];
bool dd[10000];

int main() {
    for(int i = 0;i < 10000;i++)d[i] = -NIL;
    for(int i = 0;i < 10000;i++)dd[i] = false;
    cin >> n;
    for(int i = 0;i < n;i++) {
        cin >> u >> k;
        for(int j = 0;j < k;j++) {
            cin >> v >> c;
            w.push_back(path(u,v,c));
        }
    }
    sort(w.begin(),w.end(),path::compare);
    priority_queue<pair<int,int>,vector<pair<int,int>>,std::greater<pair<int,int>> > q;
    q.push(make_pair(0,0));
    d[0] = 0;
    while(!q.empty()) {
        auto y = q.top();q.pop();
        if(dd[y.second]) continue;
        dd[y.second] = true;
        auto r = lower_bound(w.begin(),w.end(),path(y.second,0,0),path::compare);
        auto l = lower_bound(w.begin(),w.end(),path(y.second+1,0,0),path::compare);
        for(auto itr = r;itr < l;itr++) {
            if(d[itr->to] > d[itr->from] + itr->dist) {
                d[itr->to] = d[itr->from] + itr->dist;
                q.push(make_pair(d[itr->to],itr->to));
            }
        }
    }
    for(int i = 0;i < n;i++){
        cout << i << " " << d[i] << endl;
    }
}