C Program to Reverse the digits of a number in 3 Steps

C program to reverse the digits of a number ? [ In 3 Steps ]
Problem Statement : Reversing the digits of number without using mod (%) Operator ?

Prerequisite :

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

int main() {
   int num1, num2;
   char str[10];

   printf("\nEnte the Number : ");
   scanf("%d", &num1);

   sprintf(str, "%d", num1);
   strrev(str);
   num2 = atoi(str);

   printf("\nReversed Number : ");
   printf("%d", num2);

   return (0);
}

#include<stdio.h>

#include<stdlib.h>

#include<string.h>

int main() {

int num1, num2;

char str[10];

printf("\nEnte the Number : ");

scanf("%d", &num1);

sprintf(str, "%d", num1);

strrev(str);

num2 = atoi(str);

printf("\nReversed Number : ");

printf("%d", num2);

return (0);

}

Output :

Enter the Number : 123
Reversed Number : 321

1 2	Enter the Number : 123 Reversed Number : 321

Explain Logic :
Step 1 : Store Number in the Form of String

Sprintf function sends formatted output to string variable specified
Number will be stored in String variable “str”

sprintf(str,"%d",num1);

1	sprintf(str,"%d",num1);

Step 2 : Reverse the String Using Strrev Function

Strrev will reverse String
eg “1234” will be reversed as “4321”

strrev(str);

1	strrev(str);

Step 3 : Convert String to Number

[A to I ] = [ Alphabet to Integer ] = atoi
Atoi function Converts String to Integer

num2 = atoi(str);

1	num2 = atoi(str);

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C Program to Reverse the digits of a number in 3 Steps