Guessing Game with Level [C/C++]

#include<iostream>
#include<stdlib.h>
#include<stdio.h>
#include<conio.h>
main()
{
      int a,b,c,d,e,f,f1,points,ctr;
      do{
          system("cls");
          system("color 6");
          system("cls");
          do{
                        system("cls");
                        printf("Guessing Game\n");
                        /*dL1nk*/
                        printf("Level 1 = 1-10\n");
                        /*dL1nk*/
                        printf("Level 2 = 1-20\n");
                        printf("Level 3 = 1-30\n");
                        /*dL1nk*/
                        printf("Level 4 = 1-40\n");
                        printf("Level 5 = 1-50\n");
                        printf("\n\nPlease Enter Level ==>");
                        scanf("%d",&e);
                        if( e==1)
                        {
                            f=10;
                            f1=1;
                        }
                        if( e==2)
                        {
                            f=30;
                            f1=2;
                        }
                        if( e==3)
                        {
                        /*dL1nk*/
                            f=30;
                            f1=3;
                        }
                        if( e==4)
                        {
                            f=40;
                            f1=4;
                        }
                        if( e==5)
                        /*dL1nk*/
                        {
                            f=50;
                            f1=5;
                        }
                        if( e>5)
                        {
                            system("cls");
                        }
          }while(e!=1 && e!=2 && e!=3 && e!=4 && e!=5);
          srand(time(NULL));
          /*dL1nk*/
          b=1+rand()%f;
          ctr=3;
          e=b;
          /*dL1nk*/
          system("cls");
          do{
                        printf("\nGuess a Number: ");
                        scanf("%d",&a);
                        if(a>b)
                        {
                        printf("Lower Please!!\n");
                        }
                        /*dL1nk*/
                        if(a<b)
                        {
                        printf("Higher Please!!\n");
                        }
                        /*dL1nk*/
                        ctr--;
                        if( ctr==2)
                        {
                        points=15;
                        }
                        if( ctr==1)
                        {
                        points=10;   
                        }
                        if( ctr==0)
                        {
                        points=5;
                        }
                        if(a == b)
                        /*dL1nk*/
                        {
                             system("color 7");
                             printf("\n\nExcellent You Got it!!\n");
                             printf("Your Score is %d\n",points);
                             printf("\nLevel of Difficluty %d = 1-%d",f1,f);
                        }
                        }while(a!=b && ctr!=0);
          if(a!=b && ctr==0)
          {
                  system("color b");
                  printf("\n\nYou did not Get it !! \n%d is the Number!!\n",e);
                  printf("Level of Difficluty %d = 1-%d",f1,f);
                  /*dL1nk*/
                  printf("\nYour Score is 0");
          }
          printf("\n\nTry Again ? 1=Yes 2=No ==>> ");
          scanf("%d",&d);
          /*dL1nk*/
          if(d==1)
          {
                  ctr+3;
          }
          if(d==2)
          /*dL1nk*/
          {
                  break;
          }
          }while(1);
          /*dL1nk*/
          return(0);
}