Thread: Homework- Morse Code output problem

Here is the new code. Much easier to do after after reading a few chapters ahead. A lot of the stuff in this code was mentioned in class but not defined or shown which is why I didn't use it. My problem now is the while loop not ending at the null character. Any help?

Code:

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




#define STR 1000




void English_to_Morse()
{
   int len, a, b;

   char phr[STR];

   char alpha[]="abcdefghijklmnopqrstuvwxyz1234567890";
   char *morse[37]={".-","-...","-.-.","-..",".","..-.","--.","....","..",".---",
                   "-.-",".-..","--","-.","---",".--.","--.-",".-.","...","-",
                   "..-","...-",".--","-..-","-.--","--..",".----","..---",
                   "...--","....-",".....","-....","--...","---..","----.",
                   "-----","   "};
   printf("\n\tEnter in a phrase in English for encrypting\n"
          "\tor enter 'ctrl+z' to quit\n");                 


   while(*phr!='\0')
   {                
      scanf("%s", phr);
      len=strlen(phr);

      for(a=0; a<len; a++)
      {
            for(b=0; b<37; b++)
            { 

              if(tolower(phr[a])==alpha[b])
                 printf("%s ", morse[b]);
            }
      } 
   }              
}


void Morse_to_English()
{  
   int len, a, b, c;

   char phr[STR];

   char alpha[]="abcdefghijklmnopqrstuvwxyz1234567890";
   char *morse[36]={".-","-...","-.-.","-..",".","..-.","--.","....","..",".---",
                   "-.-",".-..","--","-.","---",".--.","--.-",".-.","...","-",
                   "..-","...-",".--","-..-","-.--","--..",".----","..---",
                   "...--","....-",".....","-....","--...","---..","----.",
                   "-----"};
    printf("\n\tEnter a line of Morse Code for decrypting\n\n");




    while(*phr!='\0')
    { //I struggled with getting the input to read all the characters before 
      //the space as 1 index so I came up with a for loop.  It is supposed to
      //read to the space and copy the contents of that string in the 
      //array index, but it didnt work. However, just like my other function, it will not read the null
      // character and exit the loop.    
      scanf("%s", phr);
      for(a=0; a<36; a++)
      {
         if(strcmp(phr, morse[a])==0)
            printf("%c", alpha[a]);
      }                     


    }
}


int main()
{  
   char ch;

   printf("\n\tSelect from the menu:\n"
          "\tA. English to Morse\n"
          "\tB. Morse to English\n");
   scanf("%c", &ch);


   switch(tolower(ch))
   {
      case 'a':
         English_to_Morse();
         break;
      case 'b':   
         Morse_to_English();
         break;
      default:
         break;   
   }   



   return 0;

}   

I wrote my E_to_M function before figuring out the strcmp(), I know there is some cleaning up to do and I wil do that, right now my concern is the loop ending.

Why not change that to an indexed array?

Code:

while(*phr!='\0')

to

Code:

while(phr[i]!='\0')// somewhere at the bottom of the while loop you will need to increment i

Right now *phr is never changing.

@camel-man I dont understand why you say *phr is never changing. scanf is reading in the string that is going to phr. scanf reads to the space, converts that piece, gets looped back through reads to the next space and so on until it reaches the null character. My book says that scanf reads the null character. phr has to change every time it gets looped through because the output does exactly what it should be doing. I will try the array form though and see if that works.

I think you are getting fscanf mixed up with scanf. Right now you just keep reading into the start of the array each time through the loop. phr is the address of the first element, no where in your code right now is scanf reading anything other that phr's first address.

My book says scanf will read in a string to a space and will continue from that space if it is looped. If you compile the program that is what it does. I can write a full sentence in the program and it will get translated properly. It would appear scanf is doing just what the book says all the way up to the null char.

Did you compile it and try to translate something? I thought fscanf is used for file reading like fprintf.

As an example in class our teacher wrote a program with scanf in two places. She wrote a sentence into it and had the program print out the sentence. Scanf read in the first word up to the space which was then printed to the screen and the next scanf read in the next word from the sentence and printed it, even though she wrote them both with the first scanf. That is what is happening here.

It was like this.

Code:

#include <stdio.h>


int main(void)
{
    char x[50];
    
    printf("enter a sentence\n");
    while(*x!='\0')
    {
       scanf("%s", x);
       printf("\n%s", x);
    }      


    
    return 0;


}

But again this program does not reach the null character, it does however print out every word you enter in to the string. If scanf did what you were saying then it would be printing out the first word in every sentence over and over.