3-2.c

/*
Write a function escape (s, t) 
that converts characters like new line and tab into visible escape sequences like
\n and \t as it copies the string t to s. Use a switch. 
Write a function for the other direction as well, converting escape sequences into the real characters
*/


/*
C has a variety of integer types: 
char (at least 8 bits), short (at least 16 bits), 
int (at least 16 bits), long (at least 32 bits). 
There are unsigned varieties of those. 
If you assign a value that is too large to a plain type, the results are undefined

char and int is pretty much the same a part from the six=ze of these

A string can be initialized in different ways.

1. char str[] = "GeeksforGeeks";
2. char str[50] = "GeeksforGeeks";
3. char str[] = {'G','e','e','k','s','f','o','r','G','e','e','k','s','\0'};
4. char str[14] = {'G','e','e','k','s','f','o','r','G','e','e','k','s','\0'};

or just simply assign char stri[] = "lalalalala";
*/

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

#define MAXNUMBER 100  /* number of array */

void escape_1 (char str[], char strout[]);
void reverse_escape_1 (char str[], char strout[]);

int main (){

    char str[] = "ichi \\n want to \\t this to happen ";
    printf ("original one is %s \n", str);
    char strout [MAXNUMBER];
    //escape_1(str, strout);
    reverse_escape_1(str, strout);
    printf ("converted one is %s \n", strout);
    return 0;
}

void escape_1 (char str[], char strout[]){

    int i = 0;
    int n = strlen(str);  
    printf ("strlen is %d \n", n);
    if ( n > MAXNUMBER)
        printf ("the strng is too big \n");

    for (int j = 0; j < n; j++){

        switch (str[j]){
            case '\n': 
                strout[i++] = '\\';
                strout[i++] = 'n';
                break;
            case '\b':
                strout[i++] = '\\';
                strout[i++] = 't';
                break;
            default:
                strout[i++] = str [j];
                break;
        }    
    }
        strout[i] = '\0';
        printf ("%c", strout[i]);   
}

void reverse_escape_1 (char str[], char strout[]){
    int i = 0;
    int n = strlen(str);  
    printf ("strlen is %d \n", n);
    if ( n > MAXNUMBER)
        printf ("the strng is too big \n");

    for (int j = 0; j < n; j++){

        switch (str[j]){
            case '\\':    
                j++;
                switch (str[j]){
                    case 'n': 
                        strout[i++] = '\n';
                        break;
                    case 't':
                        strout[i++] = '\t';
                        break;
                }
            break;   
            default:
                strout[i++] = str [j];
                break;
        }    
    }
        strout[i] = '\0';
        printf ("%c", strout[i]);   
}