【c语言】译密码。将字母变成其后的第4个字母，非字母不变

// 译密码。将字母变成其后的第4个字母，非字母不变

#include <stdio.h>

int main()
{
	char c;
	c = getchar();
	while( c != '\n' )
	{
		if( ( c >= 'a' && c <= 'z' ) || ( c >= 'A' && c <= 'Z' ) )
		{
			if( ( c >= 'w' && c <= 'z' ) || ( c >= 'W' && c <= 'Z' ) )
			{
				c = c - 22;
			}
			else
				c = c + 4;
		}
		printf("%c",c);
		c = getchar();
	}
	printf("\n");
	return 0;
}

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