VARIOUS METHODS TO FIND SIZE OF WITHOUT USING sizeof() OPERATOR

Sizeof is a much used operator in the C programming language. It is a compile time unary operator which can be used to compute the size of its operand. The result of sizeof is of unsigned integral type which is usually denoted by size_t. sizeof can be applied to any data-type, including primitive types such as integer and floating-point types, pointer types, or compound datatypes such as Structure, union etc.

METHODS TO FIND SIZE OF  WITHOUT USING sizeof() OPERATOR :

Program to find the size of a variable using Pointers

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#include<stdio.h> int main(void) {     int *ptr;          ptr++;          printf("Size of ptr = %d\n",ptr);     return 0; }

Program to implement your own sizeof(), Operator

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#include<stdio.h> int my_sizeof(var) {     return ((char*)(&var+1)-(char*)(&var)); } int main(void) {          int a;         printf("Value of my_sizeof(a) = %d\n",my_sizeof(a));     return 0; }

Program to find the size of a variable using Macro

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METHOD 1: #include<stdio.h> #define MY_SIZE(var)  ((char*)(&var+1)-(char*)(&var)) int main(void) {     int a;     printf("Value of my_sizeof(a) = %d\n",MY_SIZE(a));     return 0; }

        METHOD 2:




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#include<stdio.h>
#define MYSIZEOF(X) ((X*)0 +1)
int main(void)
{
    printf("%ld", MYSIZEOF(int));
    return 0;
}

Program to find the size of a variable using an Array

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#include<stdio.h> int main(void) {     int a[2];     char *p1, *p2;          p1 = &a[0];     p2 = &a[1];          printf("Size of int = %d",p2-p1);     return 0; }

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