The following program compiles successfully but doesn't give the output:
Write a program that reads data about n number of books.
Sort data about books lexicographically by title (if the title is the same, sort by publish year), and then for every book sort data about authors.
Then, read name and surname of one of the previously read authors, and print data about all books which are from that one author.

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

typedef struct
{
    char surname[101];
    char name [101];
}AUTHOR;

typedef struct
{
    char title[20];
    int year;
    int number_of_authors;
    AUTHOR *author;
}BOOK;

void read_author(AUTHOR *pa)//reads data about an author
{
    printf("surname:");
    scanf("%s",pa->surname);
    printf("name:");
    scanf("%s",pa->name);

}

void read_book(BOOK *pb)//reads data about a book
{
    printf("title:");
    scanf("%s",pb->title);
    printf("publish year:");
    scanf("%d",&pb->year);
    printf("number of authors:");
    scanf("%d",&pb->number_of_authors);
    pb->author=calloc(pb->number_of_authors,sizeof(*pb->author));
    int i;
    for(i=0;i<pb->number_of_authors;i++)
    {
        printf("%d. authors:\n",i+1);
        read_author(pb->author+i);
    }
}

int compare_authors(AUTHOR *a,AUTHOR *b)//compares authors by surname (for sorting)
{
    int i;
    for(i=0;a->surname[i] && a->surname[i] == b->surname[i];i++);
    return a->surname[i]-b->surname[i];
}

void sort_authors(AUTHOR *arr,int n)//sorts authors lexicographically
{
    int i,j;
    for(i=0;i<n-1;i++)
        for(j=i+1;j<n;j++)
        if(compare_authors(arr+i,arr+j)>0)
        {
            AUTHOR temp=arr[i];
            arr[i]=arr[j];
            arr[j]=temp;
        }
}

int compare_books(BOOK *a,BOOK *b)//compares books by title (for sorting)
{
    int i;
    for(i=0;a->title[i] && a->title[i] == b->title[i];i++);
    return a->title[i]-b->title[i];
}

void sort_books(BOOK *arr,int n)//sorts books lexicographically
{
    int i,j;
    for(i=0;i<n-1;i++)
        for(j=i+1;j<n;j++)
        {
        if(compare_books(arr+i,arr+j)>0)
    {
        BOOK temp=arr[i];
        arr[i]=arr[j];
        arr[j]=temp;
    }
    else
        if((compare_books(arr+i,arr+j) == 0) )
    {
        BOOK temp=arr[i];
        arr[i]=arr[j];
        arr[j]=temp;
    }

        }
}

void print(BOOK *pb,int n,char psurname[101],char pname[101])//prints data about books of read author (if exists)
{
    int i,j;
    scanf("%s",psurname);
    scanf("%s",pname);
    for(i=0;i<n;i++)
    {
      for(j=0;j<pb->number_of_authors;j++)
      {
        if((strcmp(pb->author[j].surname,psurname)== 0) &&
          (strcmp(pb->author[j].name,pname)==0))
        printf("%s %d %d %s %s",pb->title,pb->year,pb->number_of_authors,
               pb->author[j].surname,pb->author[j].name);
      }
    }
}

void dealloc(BOOK *pb)// free allocated memory
{
    free(pb->author);
}


int main()
{
    int i,n;
    BOOK *arr;
    char psurname[101],pname[101];
    do
    {
        printf("n=");
        scanf("%d",&n);
    }
    while(n<1);
    arr=(BOOK *)malloc(n*sizeof(BOOK));
    printf("enter books:\n");
    for(i=0;i<n;i++)
    {
        printf("%d. book:\n",i+1);
        read_book(arr+i);
    }
    sort_books(arr,n);
    for(i=0;i<n;i++)
    {
        printf("%d.",i+1);
        print(arr+i,n,&psurname,&pname);
        dealloc(arr+i);
    }
    free(arr);
    return 0;
}

Compiler gives the following warnings:
warning: passing argument 3 of 'print' from incompatible pointer type [enabled by default]|
note: expected 'char ' but argument is of type 'char ()[101]'|
warning: passing argument 4 of 'print' from incompatible pointer type [enabled by default]|
note: expected 'char ' but argument is of type 'char ()[101]'|

How to resolve these errors?

What @tinstaafl said. You are basically passing the address of a pointer, not the pointer itself in your print() statement.

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