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

typedef struct rec{
     char name[30];
     char add[30];
     int phone;
}rec;


int i;


void delete(rec*,int,int);
void insert(rec*,int*,int,int);
void display(rec*,int);
void sortstuctstr(rec*,int);


int main(){
    int n;
    int pos,elem;
    char opt;

    printf("enter number of entries: ");
    scanf("%i",&n);

    rec *arr=(rec*)calloc(n,sizeof(rec));

    for(i=0;i<n;++i){
        printf("enter name: ");
        scanf(" %[^\n]",arr[i].name);
        printf("enter address: ");
        scanf(" %[^\n]",arr[i].add);
        printf("enter phone number: ");
        scanf(" %i",&arr[i].phone);
    }

    printf("do you want to delete or insert a record? Y/N ");
    scanf(" %c",&opt);


    while(toupper(opt)!='N'){
        printf("insert(I) or delete(D) a record? ");
        scanf(" %c",&opt);

        sortstuctstr(arr,n);
        if(toupper(opt)=='I'){
            printf("enter position & number of elements to be inserted: ");
            scanf("%i%i",&pos,&elem);

            insert(arr,&n,pos,elem);
            display(arr,n);

            printf("would you like to delete or insert again? Y/N ");
            scanf(" %c",&opt);
        }

        else{
            printf("enter position that will be deleted: ");
            scanf("%i",&pos);

            delete(arr,pos,n);
            display(arr,n);

            printf("would you like to delete or insert again? Y/N ");
            scanf(" %c",&opt);
        }
    }


    sortstuctstr(arr,n);

    if(toupper(opt)=='N'){
    display(arr,n);
    return 0;
    }
}


void insert(rec* arr,int* size,int pos,int numelem){
    int range=pos+numelem-1;

    arr=realloc(arr,*size+numelem);
    for(i=*size-1;i>=pos-1;--i)
        arr[i+numelem]=arr[i];

    for(i=pos-1;i<range;++i){
        printf("enter name: ");
        scanf(" %[^\n]",arr[i].name);
        printf("enter address: ");
        scanf(" %[^\n]",arr[i].add);
        printf("enter phone number: ");
        scanf("%i",&arr[i].phone);
    }

    *size=*size+numelem;
}


void delete(rec* arr,int pos,int size){
    for(i=pos-1;i<size;++i){
        arr[i]=arr[i+1];
        if(i==size-1){
            arr[i].name[0]='\0';
            arr[i].add[0]='\0';
            arr[i].phone=0;
        }
    }
}


void sortstuctstr(rec* arr,int size){
    int lo_i=0,hi_i=size,j;
    rec temp;

	while(lo_i<hi_i){
		for(j=lo_i+1;j<hi_i;++j){
			if(strcmp(arr[lo_i].name,arr[j].name)>0){
				temp=arr[lo_i];
            	arr[lo_i]=arr[j];
            	arr[j]=temp;
			}
		}
	++lo_i;
	}
}


void display(rec* arr,int size){
    printf("name \t address \t phone number\n");
    for(i=0;i<size;++i)
        printf("%s \t %s \t %i\n",arr[i].name,arr[i].add,arr[i].phone);
}