[Beginner] Programming Challenge: 3

[jtuchscherer]

First of all: Thanks, LaRoza, for doing this.

I am late, too. But I was just preparing myself for a job interview tomorrow and thought it won't hurt to implement this challenge. I did it in Java. It lacks comments and is not quite readable, but it works.

import java.io.*;

public class Challenge {

	
	public static void main(String[] args) throws FileNotFoundException, IOException {
		// in Java 
		BufferedWriter writer1 = new BufferedWriter(new FileWriter(new File("output.txt")));
		BufferedReader reader = new BufferedReader(new InputStreamReader(new FileInputStream(new  File("bhaarat.txt")),"UTF-8" ));
		int counter = 0;
		while (reader.ready()) {
			String language = reader.readLine().split(" ")[1]; 
			if (language.startsWith("S") || language.startsWith("H") ) writer1.write(counter++ + ". " + language +"\n");  
		}
		reader.close();
		writer1.close();
		BufferedWriter writer2 = new BufferedWriter(new FileWriter(new File("/home/johannes/bhaarat.txt"),true));
		writer2.write("23. English");
		writer2.close();		
	}
}

[ratmandall]

Eh a little late but I still want to post it :\

#Opens specified file.
fileopen = open("bhaarat.txt", "a")
outlang = open("out.txt", "w")
fileopen.writelines("23. English\n")
#Close file
fileopen.close()
fileopen = open("bhaarat.txt")

for language in fileopen.read().split():

 #If a line in file opened starts with said character/s.   
 if language.startswith('S') or language.startswith('H'):

     #Write languages starting with S and H to a text file.
     outlang.writelines(language+"\n")

#Close bhaarat.txt
fileopen.close()    
#Close out.txt     
outlang.close() 

I like python makes my programs and doesn't afraid of anything.

[Nemooo]

My entry in C. It doesn't check for errors when opening the file.

/* Beginner Programming Challenge 2

   Write a program that reads bhaarat.text, and takes the languages that begin 
   with "H" or "S" and writes them to another file, named "out.text". The output 
   can be more flexible. Then have this program write "23. English" to the end 
   to continue the list in bhaarat.text. */

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

/* Remove all numbers, punctuations and spaces from the string. */
void rem_nums(char *string)
{
    const char *src = string;
    char *dst = string;

    do {
        while (*src == '0'
            || *src == '1'
            || *src == '2'
            || *src == '3'
            || *src == '4'
            || *src == '5'
            || *src == '6'
            || *src == '7'
            || *src == '8'
            || *src == '9'
            || *src == '.'
            || *src == ' ')
            ++src;
    } while ((*dst++ = *src++) != '\0');
}

/* Opens bhaarat.text and while it hasn't reached the end of the file. For each 
   line it reads, it removes the numbers and punctuations and checks if the 
   first letter is S or H. If this is the case, the language name is appended to
   out.text.

   Finally it appends '23. English' to bhaarat.text. */
int main()
{    
    char *input_file = "bhaarat.text";
    char *output_file = "out.text";
    char file_input[50];
    FILE *read_append;
    FILE *append;

    read_append = fopen(input_file, "r+a");

    while(fgets(file_input, 50, read_append) != NULL) {
        rem_nums(file_input);

        if(file_input[0] == 'H'
        || file_input[0] == 'S') {
            append = fopen(output_file, "a");
            fputs(file_input, append);
            fclose(append);
        }
    }

    fputs("\n23. English", read_append);
    fclose(read_append);

    return 0;
} 

While making this I tried to write a function, which would assign a filepointer to fopen(). If it returned NULL, the program should print an error message:

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

void openfile(FILE *f, char *filename, char *fileop)
{
    if((f = fopen(filename, fileop)) == NULL) {
        puts("Error.");
        exit(1);
    }
}

int main()
{
    FILE *f;

    openfile(f, "filename.txt", "r");
    fclose(f);

    return 0;
} 

It works fine, when an error is occuring. However if the file exists the program crashes.

[jimi_hendrix]

It works fine, when an error is occuring. However if the file exists the program crashes.

lol

[Nemooo]

Now it works, though my openfile function returns the stream instead of passing file pointer. It was more convenient that way. In the above function the first argument should've have been a pointer to a pointer (FILE **f).

/* Beginner Programming Challenge 3

   Write a program that reads bhaarat.text, and takes the languages that begin
   with "H" or "S" and writes them to another file, named "out.text". The output
   can be more flexible. Then have this program write "23. English" to the end
   to continue the list in bhaarat.text. */

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

/* Remove all numbers, periods and spaces from the string. */
void rem_nums(char *string)
{
    const char *src = string;
    char *dst = string;

    do {
        while(isdigit(*src) == 1
        || *src == '.'
        || *src == ' ')
            src++;
    } while((*dst++ = *src++) != '\0');
}

/* Open a file with the specified mode. If an error occured print the filename
   which caused the error and exit. Otherwise return the stream. */
FILE *openfile(char *filename, char *op)
{
    FILE *stream = fopen(filename, op);

    if(stream == NULL) {
        printf("Error opening %s.", filename);
        exit(1);
    }

    return stream;
}

/* Opens bhaarat.text and while it hasn't reached the end of the file. For each
   line it reads, it removes the numbers and periods and checks if the first 
   letter is S or H. If this is the case, the language name is appended to
   out.text.

   Finally it appends '23. English' to bhaarat.text. */
int main()
{
    char *input_file = "bhaarat.text";
    char *output_file = "out.text";
    char file_input[50];
    FILE *read_append;
    FILE *append;

    read_append = openfile(input_file, "r+a");

    while(fgets(file_input, 50, read_append) != NULL) {
        rem_nums(file_input);

        if(file_input[0] == 'H'
        || file_input[0] == 'S') {
            append = openfile(output_file, "a");
            fputs(file_input, append);
            fclose(append);
        }
    }

    fputs("\n23. English", read_append);
    fclose(read_append);

    return 0;
} 

[RobOrr]

Started learning Python at the weekend, and thought I'd stick my first effort at these challenges out there that I know works (my own code didn't hold up to error checks for challenge 2, so had to browse the other code submissions to help me out. )
Will hopefully have an entry for the next challenges up soon.

#!/usr/bin/python
#Filename challenge3.py
#Author: Robert Orr

import sys

#check the file exists in same directory as this program.
try:
    langfile = open('bhaarat.text', 'r')
except IOError:
    print 'Cannot locate "bhaarat.text".'
    sys.exit()
    
outfile = file('out.text', 'w')

a = 1 
while True: #while loop checks every line
    line = langfile.readline()
    if line.find('H') != -1:#look for Capital H
        linenumber, linelang = line.split('. ')
        outfile.write('%d. %s' % (a, linelang))
        a = a + 1
    if line.find('S') != -1:#look for Capital S
        linenumber, linelang = line.split('. ')
        outfile.write('%d. %s' % (a, linelang))
        a = a + 1
    if len(line) == 0:
        break

langfile.close() # it's in read mode at the moment. close and open in write.
outfile.close()
langfile = file('bhaarat.text', 'w')
langfile.seek(0, 2)
langfile.write('23. English\n')
langfile.close 

[ibuclaw]

We are hosting new challenges here. You can participate in that competition instead, rather than revive dead programming challenges.

Regards
Iain