Go: package main

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

func getScanner(fp *os.File) *bufio.Scanner {
	scanner := bufio.NewScanner(fp)
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 500001), 500000)
	return scanner
}

func getNextString(scanner *bufio.Scanner) string {
	scanner.Scan()
	return scanner.Text()
}

func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}

func main() {
	fp := os.Stdin
	if len(os.Args) > 1 {
		fp, _ = os.Open(os.Args[1])
	}

	scanner := getScanner(fp)
	writer := bufio.NewWriter(os.Stdout)

	n := getNextInt(scanner)

	g := makeGraph(n)
	for i := 0; i < n; i++ {
		u := getNextInt(scanner)
		k := getNextInt(scanner)
		for ii := 0; ii < k; ii++ {
			v := getNextInt(scanner)
			c := getNextInt(scanner)
			g[u][v] = c
		}
	}

	ans := make([]int, n)
	im := make(IntMap, 1)
	im.increment(0)
	for len(im) < n {
		min := 1 << 30
		x := -1
		for u := range im {
			for v := 0; v < n; v++ {
				if im.get(v) != 0 {
					continue
				}
				if min > ans[u]+g[u][v] {
					min = ans[u] + g[u][v]
					x = v
				}
			}
		}
		im.increment(x)
		ans[x] = min
	}

	for i := 0; i < n; i++ {
		fmt.Fprintln(writer, fmt.Sprintf("%d %d", i, ans[i]))
	}
	writer.Flush()
}

func makeGraph(n int) [][]int {
	g := make([][]int, n)
	for i := 0; i < n; i++ {
		g[i] = make([]int, n)
		for ii := 0; ii < n; ii++ {
			g[i][ii] = 1 << 30
		}
	}

	return g
}

// IntMap ...
type IntMap map[int]int

func (m IntMap) get(key int) int {
	if _, ok := m[key]; ok {
		return m[key]
	}
	return 0
}
func (m IntMap) increment(key int) {
	if _, ok := m[key]; ok == false {
		m[key] = 0
	}
	m[key]++
}

C++: #include <bits/stdc++.h>
using namespace std;
 
#define ll long long
#define vvi vector<vector<int>>
#define vec vector
#define pq priority_queue
#define all(v) (v).begin(), (v).end()
#define uniqueV(x) sort(x.begin(), x.end()); x.erase(unique(x.begin(), x.end()), x.end());
#define rep(i, n) for (int (i) = (0); (i) < (n); ++(i))
#define repp(i, m, n) for (int (i) = (m); (i) < (n); ++(i))
#define debug(x) cerr << #x << ": " << x << endl;
#define debug2(x, y) cerr<<"("<<#x<<", "<<#y<<") = "<<"("<<x<<", "<<y<<")"<<endl;
#define debug3(x, y, z) cerr<<"("<<#x<<", "<<#y<<", "<<#z<<") = "<<"("<<x<<", "<<y<<", "<<z<<")"<<endl;
#define debugB(x, y) cerr<<#x<<": "<<bitset<y>(x) << endl;
#define line() cerr << "---------------" << endl;
 
const int dx[] = {1, -1, 0, 0};
const int dy[] = {0, 0, -1, 1};
const double PI = 3.14159265358979323846;
 
template<typename T>
void printA(vector<T> &printArray, char between = ' ') {
   int paSize = printArray.size();
   for (int i = 0; i < paSize; i++) { cerr << printArray[i] << between;}
   if (between != '\n') {cerr << endl;}
}
 
// ------------------------------------------------------------------------------------------
 
struct edge { int to, cost; };
struct P { 
   int dist, number; 
   bool operator<(const P &p) const {
      return dist < p.dist;
   }
};
 
const int INF = 1e8;
int n;
vec<vec<edge>> G;
int d[111];

void printDist() {
   rep (i, n) { printf("%d %d\n", i, d[i]); }
}
 
void dijkstra(int s) {
   fill(d, d + n, INF);
   d[s] = 0;
   priority_queue<P> Q;
   Q.push({0, s});
   while (Q.size()) {
      P p = Q.top(); Q.pop();
      int v = p.number;
      if (d[v] < p.dist) continue;
      for (int i = 0; i < G[v].size(); i++) {
         edge e = G[v][i];
         if (d[e.to] > d[v] + e.cost) {
            d[e.to] = d[v] + e.cost;
            Q.push({d[e.to], e.to});
         }
      }
      // printDist();
      // line()
   }
}
 
int main() {
   // 入力
   cin >> n;
   G = vec<vec<edge>>(n);
   rep (i, n) {
      int u, k;
      cin >> u >> k;
      rep (j, k) {
         int v, c;
         cin >> v >> c;
         G[u].push_back({v, c});
      }
   }
 
   // ダイクストラ法
   dijkstra(0);
 
   // 出力
   printDist();
 
   return 0;
}

C++: #include <stdio.h>

using namespace std;


int main(){
	int n,count=0,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]=10000001;
		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=10000001;
		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 <cstdio>
#include <iostream>
using namespace std;

static const int MAX_NUM   = 101;
static const int NIL       = 10000001;
static const int NO_VISIT  = 0;
static const int NOW_VISIT = 1;
static const int END_VISIT = 2;

void SSSP(int *pMatrix, int num)
{
    int i;
    int mincost;
    int target;
    int lcost[MAX_NUM];
    int parent[MAX_NUM];
    int state[MAX_NUM];
    int *pList;

    for (i = 0; i < num; i++) {
        lcost[i]  = NIL;
        parent[i] = -1;
        state[i]  = NO_VISIT;
    }

    lcost[0]  = 0;
    parent[0] = 0;
    state[0]  = NOW_VISIT;

    for (;;) {
        mincost   = NIL;
        for (i = 0; i < num; i++) {
            if ((lcost[i] < mincost) && (state[i] != END_VISIT)) {
                target = i;
                mincost = lcost[i];
            }
        }
        if (mincost == NIL) {
            break;
        }

        state[target] = END_VISIT;
        pList = pMatrix + MAX_NUM * target;
        for (i = 0; i < num; i++) {
            if ((*(pList + i) + lcost[target]) < lcost[i]) {
                lcost[i]  = *(pList + i) + lcost[target];
                state[i]  = NOW_VISIT;
                parent[i] = target;
            }
        }
    }

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

    return;
}

int main(void)
{
    int i, j;
    int num;
    int tmp;
    int target, elem, cost;
    int matrix[MAX_NUM][MAX_NUM];

    scanf("%d", &num);
    for (i = 0; i < num; i++) {
        for (j = 0; j < num; j++) {
            matrix[i][j] = NIL;
        }
    }

    for (i = 0; i < num; i++) {
        scanf("%d %d", &target, &tmp);
        for (j = 0; j < tmp; j++) {
            scanf("%d %d", &elem, &cost);
            matrix[target][elem] = cost;
        }
    }

    SSSP(&matrix[0][0], num);

    return 0;
}

C++: #include <iostream>
using namespace std;
static const int MAX = 100;
static const int INFTY = (1<<21);
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n, M[MAX][MAX];

void dijkstra(){
    int minv;
    int d[MAX], color[MAX];

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

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

    while(1){
        minv = INFTY;
        int u=-1;
        for(int i=0;i<n;i++){
            if(minv > d[i] && color[i] != BLACK){
                u = i;
                minv = d[i];
            }
        }
        if(u==-1) break;
        color[u] = BLACK;
        for(int v=0;v<n;v++){
            if(color[v] != BLACK && M[u][v] != INFTY){
                if(d[v]>d[u]+M[u][v]){
                    d[v] = d[u] + M[u][v];
                    color[v]= GRAY;
                }
            }
        }
    }

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

int main(){
    cin >> n;
    for(int i=0;i<n;i++){
        for(int j=0;j<n;j++) M[i][j] = INFTY;
    }

    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;

}