ARRAY vs POINTER

anubala331

For ARRAY arr[4] ----value of array arr[1] or *(arr+1) where &arr[1] represents address of perticular position of array...&

arr or (arr+0) is base address of array means

VALUES----arr[0]==arr==(arr+0);;; arr[1]==(arr+1);;;; arr[2]==(arr+2);;; arr[3]==*(arr+3)

ADDRESSES..........&arr[0]==arr==(arr+0);;;;& arr[1]==(arr+1);;;;& arr[2]==(arr+2)

*******if array is of integer type then from (arr+0) to (arr+1) will jump with 4 bytes in 32 bit os...8 byte in 64 bit os depends upon size of int according to os type...

Pointers only represents its address with (ptr);;;(ptr+0);;;(ptr+1)..so on & values with ptr==(ptr+0);;;(ptr+1);;(ptr+2)

for eg.

#include<stdio.h>

int main()

{

int num[5]={34,45,66,67,68};

int i;

for(i=0;i<=4;i++)

{

printf("\naddress =%u",&num[i]);//&num=add,num[]=value

printf("\nvalue=%d %d",num[i],*(num+i));//**num+0=add so *(num+0)=value.....num[0] is a value**

printf("\nvalue=%d %d ",(i+num),i[num]);//(i+num)also a value & i[num] is same as num[i] ...i.e.a value

}

return 0;

}

~

anubala331

If i m using %s to print array using base address of array
i.e.(arr+0)..then it prints whole string but when i try to print pointer
with %s giving its base address it is not printing whole string &
giving segmentation fault......so need of printing pointer elements can
be fullfilled by using loop character by character using %c by
iNcreasing address of pointer for eg..

printf("arr=%s",arr);//prints the array

printf("ptr=%s",ptr);//give segmentation fault

so print pointer just as

while(*ptr+i != '\0')

{

printf("ptr=%c",*(ptr+i));

i++;

}

anubala331

char str1[ ];

char str2[ ]="HELLO"

str1=str2;//will give error

*BUT***

char* ptr1="hello"

char* ptr2;

ptr2=ptr1//it works fine

Whole array cannot be extracted by putting base address of one array to base address of another array.....but .....

Whole string can be get by putting base address of one pointer to another

anubala331

char str1[ ]="HELLO"

str="bye"//will give error

char *p="HELLO"

p="bye"//HELo will be overwrited....by....bye ...it works

anubala331

We can place value or string into base address of ptr ,it itself increments its continous address...we can't place whole value or string into base address of array...

ptr="I M ALWAYS LEFT BUT RIGHT"//WORKS

If name[7] is array then

name[7]="ANU BALA"//FINE

name="ANU BALA"//NOT FINE

ARRAY vs POINTER

For ARRAY arr[4] ----value of array arr[1] or *(arr+1) where &arr[1] represents address of perticular position of array...&

arr or (arr+0) is base address of array means

VALUES----arr[0]==*arr==*(arr+0);;; arr[1]==*(arr+1);;;; arr[2]==*(arr+2);;; arr[3]==*(arr+3)

ADDRESSES..........&arr[0]==arr==(arr+0);;;;& arr[1]==(arr+1);;;;& arr[2]==(arr+2)

*******if array is of integer type then from (arr+0) to (arr+1) will jump with 4 bytes in 32 bit os...8 byte in 64 bit os depends upon size of int according to os type...

Pointers only represents its address with (ptr);;;(ptr+0);;;(ptr+1)..so on & values with *ptr==*(ptr+0);;;*(ptr+1);;*(ptr+2)

for eg.

#include<stdio.h>

int main()

{

int num[5]={34,45,66,67,68};

int i;

for(i=0;i<=4;i++)

{

printf("\naddress =%u",&num[i]);//&num=add,num[]=value

printf("\nvalue=%d %d",num[i],*(num+i));//num+0=add so *(num+0)=value.....num[0] is a value

printf("\nvalue=%d %d ",*(i+num),i[num]);//*(i+num)also a value & i[num] is same as num[i] ...i.e.a value

}

return 0;

}

~

~

printf("arr=%s",arr);//prints the array

printf("ptr=%s",ptr);//give segmentation fault

so print pointer just as

while(*ptr+i != '\0')

{

printf("ptr=%c",*(ptr+i));

i++;

}

char str1[ ];

char str2[ ]="HELLO"

str1=str2;//will give error

***************************************BUT*****************************************

char* ptr1="hello"

char* ptr2;

ptr2=ptr1//it works fine

Whole array cannot be extracted by putting base address of one array to base address of another array.....but .....

Whole string can be get by putting base address of one pointer to another

char str1[ ]="HELLO"

str="bye"//will give error

char *p="HELLO"

p="bye"//HELo will be overwrited....by....bye ...it works

We can place value or string into base address of ptr ,it itself increments its continous address...we can't place whole value or string into base address of array...

ptr="I M ALWAYS LEFT BUT RIGHT"//WORKS

If name[7] is array then

name[7]="ANU BALA"//FINE

name="ANU BALA"//NOT FINE

Howdy, Stranger!

Categories

VALUES----arr[0]==arr==(arr+0);;; arr[1]==(arr+1);;;; arr[2]==(arr+2);;; arr[3]==*(arr+3)

Pointers only represents its address with (ptr);;;(ptr+0);;;(ptr+1)..so on & values with ptr==(ptr+0);;;(ptr+1);;(ptr+2)

printf("\nvalue=%d %d",num[i],*(num+i));//**num+0=add so *(num+0)=value.....num[0] is a value**

printf("\nvalue=%d %d ",(i+num),i[num]);//(i+num)also a value & i[num] is same as num[i] ...i.e.a value

*BUT***