Question

The following code is written to select some data from one file and copy into another, but I am getting error “Incompatible types in assignment” at notified position.I am unable to figure out what is causing this error. I will be glad to get your assistance.

#include <stdio.h>
#include <stdlib.h>

int main()
{
     FILE *myfile;
     myfile=fopen("write.txt","a");

char *name;
int id,i=0,check,*w,n=0;
if(myfile)
{
  do
  {
    printf("Enter ID and Name of the student\n");
    scanf("%d%s",&id, name);
    fprintf(myfile,"%d$ %s@", id, name);
    printf("Are there any more students [y/n]");
  }while(getch()=='y');
  fclose(myfile);
}
printf("Do you want to shortlist the students [y/n]?");
if(getch()=='y')
{
    myfile=fopen("write.txt","r");
    while(check!=EOF)
    {
        check=getc(myfile);
        i++;
        if(check=='%')
            n++;
    }
    fclose(myfile);

    myfile=fopen("write.txt","r");

    int x[i-1];
    char car[n][20];

    int yolo,y=0,q=0,j,h,temp;

    for(j=0;j<i;j++)
    {
        x[j]=getc(myfile);
        if(x[j]=='$')
        {
            w[q]=x[j-1];
            yolo=temp=j;
            q++;
        }
        else
        if(x[j]=='@')
        {
            yolo++;
            for(h=0;h<j-temp;h++)
                car[y]=(char)x[yolo]; // ERROR
            y++;
        }
    }
    fclose(myfile);
    //char data= new char[i++];
    //fscanf();
    myfile=fopen("shortlisted.txt","a");

    if(myfile)
    {
        printf("Type the ID of the student you want to shortlist:\n");
        scanf("%d",id);
    }
}
else
    printf("The file you specified doesn't exists");
printf("Hello world!\n");
return 0;

}

This code needs a little work at the moment but I want to remove all possible error before finalizing the code

Regards

Answer 1

car[y] is an array of chars whereas (char)x[yolo] is just a char. You’re trying to assign a char to an array of chars.

If you want to set the first character in car[y] to the value of x[yolo], just use car[y][0] = (char)x[yolo]. Note that that won’t convert x[yolo] into a char representation of an int. To get a char * representation of an integer, you’ll want to use itoa. But even then, a straight assignment won’t work: you’ll have to use strcpy.

EDIT: it has been brought to my attention that it’s better to use sprintf than itoa.