understanding malloc()

//understanding malloc()
#include <stdio.h>
#include <stdlib.h>

int main()
{
    int *x ;//pointer declaration
    x= (int*)malloc(10*sizeof(int));//allocates the memory for 10 integers(10x4=40)
                                    // to heap

    if(x==NULL)//tests whether the memory is available
    {
        printf("error in allocating");//displays error if no memory
    }
    else
    {
    printf("%d\n", sizeof(x));//prints value 4. Because the
                            //sizeof thinks what memory each value/integer will occupy
    }
    return 0;
}

off topics tips/tricks

1) understanding about malloc() function:

                                                                                                                    solution

                                                                                                                    solution


2)to understand free() function

                                                                                                                  solution

3)WAP to understand malloc() using struct pointer.

                                                                                                                   solution

                                                                                                                   solution

program to understand about malloc() function

//understanding malloc()
#include <stdio.h>
#include <stdlib.h>

int main()
{
    int *x ;
    x= (int*)malloc(sizeof(int));//allocates the memory(4 bytes) to heap
    if(x==NULL)//tests whether the memory is available
    {
        printf("error in allocating");//displays error if no memory
    }
    else
    {
        *x=10;//assigns value
    printf("%d\n", *x);//prints value 10
    }
    return 0;
}

WAP to input a string and to print its address(character's) with its value.

//progrm to print address and value of a string given by user.
#include <stdio.h>
int main()
{
    char name[30];
    char *p;
    int i=0;
    printf("enter the string\n");
    scanf("%s",name);
    p=name;//assigning base address
    while(*p!='\0')//condition testing
    {
    printf("the address=%d and value=%c\n",p+i,*p);//printing value and address
   *p++;//changing the value
    i++;//changing the value of i
    }
 

    return 0;
}

python program to print sum of two numbers 3 and 4

type following code in IDLE.
-----------------------------------------
#program to print sum of two numbers 3 and 4 #comment of program

a=3   #assigning value to a variable
b=5    #assigning value to variable
sum=a+b#forumaltion
print("the sum of two numbers is=\n",sum)#printing the sum
print("the sum of numbers",a,"and",b,"is",sum)#we can print values by putting comma

python program to print hello python with single line comment

type following code in IDLE
------------------------------------------------------------------

#program to print python #comment of program

print("hello python")   #prints the string hello python

python program to print hello python with comment

"""
first program in python  #multi line comment using triple quotes
"""
print("hello python")   #prints the string hello python