Write a program to reverse a string, concatenate two strings Comparision of String

Program to Reverse a String

#include <stdio.h>  
#include <string.h>  
int main(){  
    char str[40]; // declare the size of character string  
    printf (" \n Enter a string to be reversed: ");  
    scanf ("%s", str);  
      
    // use strrev() function to reverse a string  
    printf (" \n After the reverse of a string: %s ", strrev(str));  
    return 0;  
}  

Program to Concatenate Two Strings

#include <stdio.h>
int main() {
  char s1[100] = "VTU ", s2[] = "Updates";
  int length, j;

  // store length of s1 in the length variable
  length = 0;
  while (s1[length] != '\0') {
    ++length;
  }

  // concatenate s2 to s1
  for (j = 0; s2[j] != '\0'; ++j, ++length) {
    s1[length] = s2[j];
  }

  // terminating the s1 string
  s1[length] = '\0';

  printf("After concatenation: ");
  puts(s1);

  return 0;
}

Program to Compare Two Strings

#include <stdio.h>  
#include<string.h>  
int main()  
{  
   char str1[50];  // declaration of char array  
   char str2[50];  // declaration of char array  
   int value; // declaration of integer variable  
   
   printf("Enter the first string : ");  
   scanf("%s",str1);  
   printf("Enter the second string : ");  
   scanf("%s",str2);  
   
   // comparing both the strings using strcmp() function  
   value = strcmp(str1,str2);  
   if(value == 0)  
   printf("strings are same");  
   else  
   printf("strings are not same");  
   return 0;  
}