"Huawei OJ" string encryption and decryption

Describe:	Title Description 1, the input string is added and decrypted, and output. 2 Encryption methods are: When the content is an English letter is replaced with the letter of the latter letter, while the letter conversion case, such as the letter A is replaced by B, the letter z is replaced by A; When the content is a number, the number is added 1, such as 0 to replace the replacement 2,9 replacement 0; Other characters do not change. 3, the decryption method is the inverse process of encryption. Interface Description: Implement interfaces, each of which implements 1 basic operations: void Encrypt (char aucpassword[], char aucresult[]): Implements string encryption in this function and outputs Description 1. The string ends with a. 2, string maximum 100 characters. int Unencrypt (char result[], char password[]): Implement string decryption and output in this function Description 1. The string ends with a. 2, string maximum 100 characters.
Knowledge Points:	String
Source of the topic:	Internal finishing
Practice Stage:	Primary
Run time limit:	10Sec
Memory Limit:	128MByte
Input:	Enter a description Enter a string of passwords to encrypt Enter a string of password encryption
Output:	Output description Output encrypted characters Output decrypted characters
Sample input:	ABCDEFG BCDEFGH
Sample output:	BCDEFGH ABCDEFG

#include "stdio.h"
#include "string.h"
#include "ctype.h"
Void Change (char str[])
{
	int l=0, i=0, j=0;
	L = strlen (str);
	for (i = 0; i < l; i++)
	{
	if (Isupper (Str[i]))
	str[i] = (Str[i] + 32-1-' a ' + +)% 26+ ' a ';
	else if (Islower (Str[i]))
	str[i] = (Str[i]-+ 1-' a ' + +)% + ' a ';
	else if (IsDigit (Str[i]))
	str[i] = (Str[i] + 1-' 0 ' + Ten)% + ' 0 ';

	}
	for (i = 0; i < l; i++)
	{
		printf ("%c", Str[i]);
	}
	printf ("\ n");
}
int main ()
{
	char str1[1000],str2[1000];
	Gets (STR1);
	Gets (STR2);
	Change (STR1);
	Change (STR2);
	return 0;

}