Go: package main

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

type Item struct {
	value    int // The value of the item; arbitrary.
	priority int // The priority of the item in the queue.
	// The index is needed by update and is maintained by the heap.Interface methods.
	index int // The index of the item in the heap.
}
type PriorityQueue []*Item

func (pq PriorityQueue) Len() int { return len(pq) }
func (pq PriorityQueue) Less(i, j int) bool {
	return pq[i].priority < pq[j].priority
}
func (pq PriorityQueue) Swap(i, j int) {
	pq[i], pq[j] = pq[j], pq[i]
	pq[i].index = i
	pq[j].index = j
}
func (pq *PriorityQueue) Push(x interface{}) {
	n := len(*pq)
	item := x.(*Item)
	item.index = n
	*pq = append(*pq, item)
}
func (pq *PriorityQueue) Pop() interface{} {
	old := *pq
	n := len(old)
	item := old[n-1]
	item.index = -1 // for safety
	*pq = old[0 : n-1]
	return item
}

type Q struct {
	pq *PriorityQueue
	ds map[int]int // It has always same value as pq. For random access.
}

func newQ() *Q {
	pq := new(PriorityQueue)
	heap.Init(pq)
	return &Q{
		pq: pq,
		ds: make(map[int]int),
	}
}
func (q *Q) pop() (u, d int) {
	item := heap.Pop(q.pq).(*Item)
	delete(q.ds, item.value)
	return item.value, item.priority
}
func (q *Q) get(u int) (int, bool) { // returns d
	d, ok := q.ds[u]
	return d, ok
}
func (q *Q) set(u, d int) {
	q.ds[u] = d
	for _, item := range *q.pq {
		if item.value != u {
			continue
		}

		item.priority = d
		heap.Fix(q.pq, item.index)
		return
	}
	heap.Push(q.pq, &Item{
		priority: d,
		value:    u,
	})
}
func (q *Q) len() int {
	return len(q.ds)
}

func main() {
	r := bufio.NewReader(os.Stdin)

	var n int
	fmt.Fscan(r, &n)
	cs := make([]map[int]int, n) // []v_i -> c_i
	for h := 0; h < n; h++ {
		var u, k int
		fmt.Fscan(r, &u, &k)
		m := make(map[int]int)
		for i := 0; i < k; i++ {
			var v, c int
			fmt.Fscan(r, &v, &c)
			m[v] = c
		}

		cs[u] = m
	}

	q := newQ()
	q.set(0, 0)
	visited := make(map[int]struct{})
	out := make([]int, n)

	for q.len() > 0 {
		u, d := q.pop()
		for uu, c := range cs[u] {
			// Consider the connection between u and uu.
			if _, ok := visited[uu]; ok {
				continue
			}
			dd := d + c
			if d, ok := q.get(uu); !ok || d > dd {
				q.set(uu, dd)
			}
		}

		out[u] = d
		visited[u] = struct{}{}
	}

	for u, d := range out {
		fmt.Println(u, d)
	}
}

C++: #include <stdio.h>

using namespace std;


int main(){
	int n,count,t,min,min_index,tmp,left_node,right_node,dist;
	scanf("%d",&n);
	int distance[n][n],P[n];

	for(int i=0;i<n;i++){
		for(int k=0;k<n;k++)distance[i][k]=100001;
		P[i]=0;
	}
	distance[0][0] = 0;
	P[0]=1;

	for(int i=0;i<n;i++){
		scanf("%d %d",&left_node,&tmp);
		for(int k=0;k<tmp;k++){
			scanf("%d %d",&right_node,&dist);
			distance[left_node][right_node] = dist;
		}
	}

	while(count<n-1){

		min=100001;
		for(int i=1;i<n;i++){
			if(P[i]==0&&distance[0][i]<min){
				min_index = i;
				min = distance[0][i];
			}
		}
		t = min_index;
		P[t]=1;
		count++;

		for(int i=0;i<n;i++){
			if(distance[0][i] > distance[0][t]+distance[t][i]){
				distance[0][i]=distance[0][t]+distance[t][i];
			}
		}
	}

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

    return 0;
}

C++: #include <bits/stdc++.h>
#define INF 1e9
using namespace std;
int M[100][100],d[100],p[100];
bool vist[100]={0};
void prim(int n){
	for(int i=0;i<n;i++) d[i] = INF;
	d[0] = 0;
	p[0] = -1;
	int mincost, u;
	while(1){
		mincost = INF;
		for(int i=0;i<n;i++)
			if(!vist[i] && d[i]<mincost)
				mincost = d[i], u = i;
		if(mincost == INF) break;
		vist[u] = 1;
		for(int i=0; i<n; i++)
			if(!vist[i] && M[u][i]!=-1 && d[u]+M[u][i]<d[i])
				d[i] = M[u][i] + d[u],
				p[i] = u;
	}
}
int main()
{	
	memset(M,-1,sizeof(M));
	int n,du,v,u; cin>>n;
	for(int i = 0;i < n;i++){
		scanf("%d%d",&v,&du);
		while(du--)
			scanf("%d",&u),
			scanf("%d",&M[v][u]);
	}
	prim(n);
	for(int i=0; i<n; i++)
		printf("%d %d\n",i,d[i]);
	return 0;
}

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

#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP0(i,n) for(int i=0, i##_len=(n); i<i##_len; ++i)
#define REP1(i,n) for(int i=1, i##_len=(n); i<=i##_len; ++i)
#define RREP0(i,n) for(int i=n-1; i>=0; --i)
#define RREP1(i,n) for(int i=n; i>=1; --i)

#define SORT(c) sort((c).begin(),(c).end())
#define whole(f,x,...) ([&](decltype((x)) whole) { return (f)(begin(whole), end(whole), ## __VA_ARGS__); })(x)
#define PB push_back
#define MP make_pair
#define SZ(a) int((a).size())
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define CLR(a) memset((a), 0 ,sizeof(a))

inline int toInt(string s) {int v; istringstream sin(s);sin>>v;return v;}
template<class T> inline string toString(T x) {ostringstream sout;sout<<x;return sout.str();}
int gcd(int a,int b){return b?gcd(b,a%b):a;}
int dx[4]={1,0,-1,0};
int dy[4]={0,1,0,-1};

typedef long long LL;
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<string> VS;
typedef pair<int, int> PII;

const int INTINF = 2147483647;
const LL LLINF = 9223372036854775807;
const double EPS = 1e-10;
const double PI  = acos(-1.0);
const int WHITE = 0;
const int GRAY = 1;
const int BLACK = 2;
const int MAX = 100;
int n, M[MAX][MAX];
int d[MAX], color[MAX];

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


void dijkstra(){
  int minv;

  REP0(i,n){
    d[i] = INTINF;
    color[i] = WHITE;
  }

  d[0] = 0;
  color[0] = GRAY;

  while (1) {
    minv = INTINF;
    int u = -1;
    // 未確定頂点のうち最も近いもの := u を選んで確定
    REP0(i,n){
      if ( minv > d[i] && color[i] != BLACK ){
        u = i;
        minv = d[i];
      }
    }
    if ( u == -1 ) break;
    color[u] = BLACK;
    // uから到達可能な未確定頂点を選んで最短距離を更新していく
    REP0(v,n){
      if ( color[v] != BLACK && M[u][v] != INTINF) {
        if ( d[v] > d[u] + M[u][v] ) {
          d[v] = d[u] + M[u][v];
          color[v] = GRAY;
        }
      }
    }
  }
}



void input() {
  std::cin >> n;
  REP0(i,n) REP0(j,n) M[i][j] = INTINF;

  int u, k, v, c;
  REP0(i,n){
    std::cin >> u >> k;
    REP0(j,k){
      std::cin >> v >> c;
      M[u][v] = c;
    }
  }
}


void output(){
  REP0(i,n){
    std::cout << i << " " << ( d[i] == INTINF ? -1 : d[i] ) << '\n';
  }
}


int main(int argc, char const *argv[]) {
  input();
  dijkstra();
  output();
  return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;
#define rp(i,j) for(long long i=0;i<j;i++)
#define rep(i,j,k) for(long long i=j;i<k;i++)
#define mod 1000000007
#define NIL -1
#define MAX 100
static const int INFTY=(1<<21);
typedef long long ll;
int n,u;
int M[MAX][MAX];
int d[MAX];
int color[MAX];
void dijkstra(){
    rp(i,n){
        d[i]=INFTY;
        color[i]=0;
    }
    d[0]=0;
    color[0]=1;
    while(1){
        int minv=INFTY;
        rp(i,n){
            if(color[i]!=2&&d[i]<minv){
                minv=d[i];
                u=i;
            }
        }
        if(minv==INFTY)break;
        color[u]=2;
        rp(i,n){
            if(d[u]+M[u][i]<d[i]){
                d[i]=d[u]+M[u][i];
                color[i]=1;
            }
        }

    }
}
int main(){
    int u,k,v,c;
    cin>>n;
    rp(i,n){
        rp(j,n)M[i][j]=INFTY;
        cin>>u>>k;
        rp(j,k){
            cin>>v>>c;
            M[u][v]=c;
        }
    }
    dijkstra();
    rp(i,n)cout<<i<<" "<<d[i]<<endl;
}