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Simple algorithm problem I want to write a simple encryption program that does the following: Take a file as input (redirected at the Unix prompt), and encrypt/decrypt and print each character as directed. Convert uppercase characters to the lowercase character 3 down in the alphabet, EXCEPT A, B, C which become x, y, z respectively. Convert lowercase characters to the uppercase character 2 down in the alphabet, EXCEPT a, b which become Y, Z respectively. Convert all punctuation characters (ASCII 33-47, 58-64, 91-96, and 123-126) to the punctuation character 1 down in the ASCII chart; e.g., 34 " becomes 33 !, 35 # becomes 34 ", 58 : becomes 47 /;
EXCEPT 33 ! which becomes 126 ~.
here is some sample output:
now my code looks like:Code:If the file which is redirected in contains the following text: ABCDEFGHIJKLMNOPQRSTUVWXYZ abcdefghijklmnopqrstuvwxyz 01234567890 The quick brown fox jumped over the lazy dogs. !"#$%&'()*+,-./:;<=>?@[\]^_`{|}~ Then the output of the program should be:: xyzabcdefghijklmnopqrstuvw YZABCDEFGHIJKLMNOPQRSTUVWX 01234567890 qFC OSGAI ZPMUL DMV HSKNCB MTCP RFC JYXW BMEQ- ~!"#$%&'()*+,-./:;<=>?@[\]^_`{|}
any help would be greatly appreciated and thank you in advance. This has been bugging me all night long.Code:#include <stdio.h> #include <ctype.h> #define TRUE 1; #define False 0; //function prototypes char convert(char inputChar, int *whtSpc, int *charCnt); void display(int numWords, int whtSpc); char convUpper(char inputChar); char convLower(char inputChar); char convPunct(char inputChar); int main(void) { //initialize vars char inputChar; char convertedChar; int charCnt = 0; int numWords = 0; int whtSpc = 0; //while((inputChar = getchar()) != EOF) //{ convertedChar = convert(inputChar, &whtSpc, &charCnt); //}//end while display(numWords, whtSpc); return 0; }//end of main char convert(char inputChar, int *whtSpc, int *charCnt) { char convertedChar; while((inputChar = getchar()) != EOF) { if(isalnum(inputChar) == 1) { charCnt++; } else if(isspace(inputChar) == 1) { charCnt--; } if((charCnt >0) && (isspace(inputChar))) { whtSpc++; }//end if if(isupper(inputChar)) { convertedChar = convLower(inputChar); }//end if else if(islower(inputChar)) { convertedChar = convUpper(inputChar); }//end if else if(ispunct(inputChar)) { convertedChar = convPunct(inputChar); } printf("%c", convertedChar); }//end of while return convertedChar; }//end of convert() ///////////////////////////////////////////////////////////////////////////// //Name: display() //Purpose: displays the results of the conversion ///////////////////////////////////////////////////////////////////////////// void display(int numWords, int whtSpc) { printf("\n%20s%20s", "Description", "Quantity"); printf("\n%20s%20s", "-----------", "--------"); printf("\n%20s%20d", "Words", numWords); printf("\n%20s%20d", "Whitespace", whtSpc); printf("\n\n"); }//end of display() ////////////////////////////////////////////////////////////////////////////// //Name: convUpper() //Purpose: converts lowercase chars to an uppercase char 2 down ////////////////////////////////////////////////////////////////////////////// char convUpper(char inputChar) { char convertedChar = inputChar; if(inputChar >= 97 && inputChar <=98) { if(inputChar == 97) { convertedChar = 'Y'; } else if(inputChar == 98){ convertedChar = 'Z'; } }//end if if(!(isupper(convertedChar))) { convertedChar = toupper(inputChar + 2); }//end if return convertedChar; }//end of convUpper() ////////////////////////////////////////////////////////////////////////////// //Name: convLower() //Purpose: converts uppercase chars to a lowercase char 3 down ///////////////////////////////////////////////////////////////////////////// char convLower(char inputChar) { char convertedChar = inputChar; if(inputChar >= 65 && inputChar <= 67) { if(inputChar == 65) { convertedChar = 97; } else if(inputChar == 66){ convertedChar = 98; } else if(inputChar == 67){ convertedChar = 99; } }//end if if(!(islower(convertedChar))) { convertedChar = tolower(inputChar + 3); }//end if return convertedChar; }//end of convLower() ///////////////////////////////////////////////////////////////////////////// //Name: convPunct() //Purpose: wrap the puctioation arround + 1 times ///////////////////////////////////////////////////////////////////////////// char convPunct(char inputChar) { char convertedChar; if(inputChar == '!') { convertedChar = '~'; } else { convertedChar = (int)inputChar - 1; } return convertedChar; }//end of convPunct()
Originally Posted by computerfreaks 
