TP5 universite paris diderot informatique

TP5.cs

using System;
using System.Linq;

namespace Main {
  public class TP5 {
    static Random rand = new Random();
    static int randRange(int a, int b)
    {
      return (rand.Next(b - a - 1) + a);
    }
    public static void Main(string[] args) {
      int[][] g = {new int[]{0, 1, 0}, new int[]{1, 0, 0}, new int[]{0, 0, 0}};
      Console.WriteLine(deepToString(CreateGraph(5)));
      Console.WriteLine(friends_nbr(g, 0));
      Console.WriteLine(toString(friends(g, 0)));
      Console.WriteLine(toString(popular(g)));
      int[][] gr = {new int[]{0, 1, 1}, new int[]{1, 0, 1}, new int[]{0, 1, 1}};
      Console.WriteLine(toString(common_friends(gr, 0, 1)));
      int[][] gr2 = add_user(gr, new int[]{0, 1, 2, 3});
      Console.WriteLine(deepToString(gr2));
      Console.WriteLine(toString(popular_noms(g, new String[]{"a", "b", "c"})));
      Console.WriteLine("abc");
    }
    static string deepToString(int[][] a)
    {
      return "[" + String.Join(",", a.Select(p => toString(p)).ToArray()) + "]";
    }
    static string toString(int[] a)
    {
      return "[" + String.Join(",", a.Select(p => p.ToString()).ToArray()) + "]";
    }
    static string toString(string[] a)
    {
      return "[" + String.Join(",", a.Select(p => p).ToArray()) + "]";
    }

    static int[][] CreateGraph(int N)
    {
      int n = randRange(0, N);
      int[][] Graph = new int[N][];
      for (int i = 0; i < N; i++) {
        Graph[i] = new int[N];
      }

      while (n != 0)
      {
        int i = randRange(0, N), j = randRange(0, N);
        if (0 == Graph[i][j] && i != j)
        {
          Graph[i][j] = Graph[j][i] = 1;
          n--;
        }
      }

      return Graph;
    }
    
    static int friends_nbr(int[][] R, int a)
    {
      int ret = 0;
    
      foreach (int c in R[a])
        ret += c;
    
      return ret;
    }
    
    static int[] friends(int[][] R, int a)
    {
      int[] f = new int[friends_nbr(R, a)];
      int c = 0;
    
      for (int i = 0; i < R[a].Length; i++)
        if (1 == R[a][i])
          f[c++] = i;
    
      return f;
    }
    
    static int[] popular(int[][] R)
    {
      int[] ret_tmp = new int[R.Length];
      int max_friend = 0;
      int l = 0;
    
      for (int a = 0; a < R.Length; a++)
      {
        int c = friends_nbr(R, a);
    
        if (c > max_friend)
        {
          l = 1;
          ret_tmp[0] = a;
          max_friend = c;
        }
        else if (c == max_friend)
          ret_tmp[l++] = a;
      }
    
      int[] ret = new int[l];
    
      for (; --l >= 0;)
        ret[l] = ret_tmp[l];
    
      return ret;
    }
    
    static int[] common_friends(int[][] R, int a, int b)
    {
      int f_a = friends_nbr(R, a), f_b = friends_nbr(R, b);
      int[] f = new int[(f_a > f_b ? f_a : f_b) - R[a][b]];
      int c = 0;
    
      for (int i = 0; i < R[a].Length; i ++)
        if (1 == R[a][i] && 1 == R[b][i])
          f[c++] = i;
    
      return f;
    }
    
    static int[][] add_user(int[][] R, int[] t)
    {
      int u = R.Length;
      int[][] Ret = new int[u + 1][];
      for (int i = 0; i < u + 1; i++) {
        Ret[i] = new int[u + 1];
      }
    
      for (int i = 0; i < u; i++)
        for (int j = 0; j < u; j++)
          Ret[i][j] = R[i][j];
      foreach (int f in t)
        if (0 <= f && f < u)
          Ret[f][u] = Ret[u][f] = 1;
    
      return Ret;
    }
    
    static string[] popular_noms(int[][] R, string[] noms)
    {
      int[] ret_tmp = new int[R.Length];
      int max_friend = 0;
      int l = 0;
    
      for (int a = 0; a < R.Length; a++)
      {
        int c = friends_nbr(R, a);
    
        if (c > max_friend)
        {
          l = 1;
          ret_tmp[0] = a;
          max_friend = c;
        }
        else if (c == max_friend)
          ret_tmp[l++] = a;
      }
    
      string[] ret = new string[l];
    
      for (; --l >= 0;)
        ret[l] = noms[ret_tmp[l]];
    
      return ret;
    }
  }
}