file handling

 #include<stdio.h>

#include<stdlib.h>

void write(int num)

{

FILE *fp;

fp=fopen("storeNum.txt","w");

fprintf(fp,"%d",num);

fclose(fp);

printf("succesfully stored");

printf("\nQuitting the program....");

}

void display(void)

{

   system("clear");

   int num3;

   FILE *fp;

   fp=fopen("storeNum.txt","r");

   fscanf(fp,"%d",&num3);

   printf("Displaying numbee\n");

   printf("%d\n",num3);

   fclose(fp);

   printf("Quitting the program....");

}

void check(int num2)

{ int num4;

   int x;

   FILE *fp;

   fp=fopen("storeNum.txt","r");

   fscanf(fp,"%d",&num4);

   if(num2==num4)

   {

   printf("It already exist\n");

   printf("Quitting the program....");

   fclose(fp);

   }

   else

   {

   printf("Not exist \nPress\n1.to save\n ");

   scanf("%d",&x);

   system("clear");

   if(x==1)

   {

      fp=fopen("storeNum.txt","w");

      fprintf(fp,"%d",num2);

      fclose(fp);

      printf("succesfully saved");

   }

   printf("Quitting the program....");

   }

}

int main()

{

   int numLo,numCheck,choice;

   printf("Enter\n1.To store a number\n2.To display a number\n3.To check if that number is already stored\n");

   scanf("%d",&choice);

   switch(choice)

   {

      case 1:

      system("clear");

      printf("Enter a number to store\t");

      scanf("%d",&numLo);

      write(numLo);

      break;

      case 2:

      display();

      break;

      case 3:

      system("clear");

      printf("Enter a number to check\t");

      scanf("%d",&numCheck);

      check(numCheck);

      break;

      default :

      printf("Quitting the program....");

      break;

   }

}