Problem [WILL NOT PRESENT IT AT SPOJ]

Delshire 2014-09-16 23:09:09 UTC #1

I've given an answer to the code but i can not understand some parts of it, the ones what i do not understand i mark it on [color=#FF0000]red[/color]

include

define IN 1

define OUT 0

define MAXLENGTH 11

int main()
{
int i = 0;
int j =0; /* i and j are simply index counters */
int c = 0;
int nchar = 0; /* number of characters in a word */
int inspace = IN; /* a flag to know whether we are inside of outside the word */
int wordlen[MAXLENGTH]; /* counts how many words of a particular length we have seen */

[color=#FF0000] for(i = 0; i < MAXLENGTH; ++i) //What are we doing here? Why setting up all the array to 0?
wordlen[i] = 0;[/color]

while((c = getchar()) != EOF) [color=#000000]// While you do not end writing --->[/color]
{
if(c == ' ' || c == '\t' || c == '\n') [color=#000000]//IF the char you wrote is a blank space, tab or new line[/color]
{
if (inspace == OUT) [color=#FF0000] //From here i do not understand what is going on[/color]
[color=#FF0000] {
if(nchar < MAXLENGTH)
++wordlen[nchar];
}

  inspace = IN;
  nchar = 0;
}
  else
{
  ++nchar;
  if(c == '"' || c == '\'')
    --nchar;
  inspace = OUT;                  [b]//Until here[/b]
}[/color]
}

/* printing the Horizontal-Histogram */
for(i = 1; i < MAXLENGTH; ++i)
{
printf("%2d| ", i);
for(j = 0; j < wordlen[i]; ++j)
putchar('*');

  putchar('\n');
}

return 0;
}

My request is if someone could explain me those lines of code, i can not get it

Thanks!!

leppyr64 2014-09-17 12:48:37 UTC #2

When an array is created in C it is uninitialized. The value at wordlen[2] could be 8565 for all we know.

As for the rest of the code, these are the keys.

int nchar = 0; /* number of characters in a word */
int inspace = IN; /* a flag to know whether we are inside of outside the word */

If c is a whitespace character then we know what we are in a space (inspace). If the previous character was not a whitespace then we have just finished a word and need to record it. The number of characters in the current word is 0.

If c is not a whitespace character then we know that we are not in a space, increment the number of characters in the current word.

Delshire 2014-09-17 22:05:52 UTC #3

Thank you very much! I did not know that about arrays, now all becames clearer. Thanks!!

PS : What are we actually increasing here?

if(nchar < MAXLENGTH)
++wordlen[nchar];
}

If it does not exceed the MAXLENGTH then what happens? We add in one index of the array the number of characters that a word have?

Thanks mate!

leppyr64 2014-09-17 22:28:26 UTC #4

wordlen[5] will be the number of words with length 5. The code you posted occurs in the white space immediately following a word of length nchar. It increases the number of words with length nchar.

Cheers!

Delshire 2014-09-20 14:53:34 UTC #5

Thanks leppy for all the help!