Count words in a user-input string in C - c

Question

So, we were given this program in class. "Write a Program in C to count the number of words in a sentence input by the user."
This is what i could come up with, but the number of words is always one less than what is the correct number. My teacher told everyone to just add 1 to the word count before printing it. I think it has a bug, if we don't enter any words, i.e. , press Enter instead of typing,the program suggested by my teacher would still give word count as 1 not 0. Do you know of any way to get proper word count without just adding 1 at the end?
Code:
My code(giving 1 less than correct) :
#include <stdio.h>
#include <string.h>
void main()
{
char s[200];
int count = 0, i;
printf("enter the string\n");
gets(s);
for (i = 0;i<strlen(s);i++)
{
if (s[i] == ' ')
count++;
}
printf("number of words in given string are: %d\n", count);
}

Answer 1

It's just that you're counting spaces, this would also be incorrect if the user ended the string with a bunch of spaces. Try something like this:
#include <stdio.h>
#include <string.h>
void main()
{
char s[200];
int count = 0, i;
int foundLetter = False;
printf("enter the string\n");
gets(s);
for (i = 0;i<strlen(s);i++)
{
if (s[i] == ' ')
foundLetter = False;
else
{
if (foundLetter == False)
count++;
foundLetter = True;
}
}
printf("number of words in given string are: %d\n", count);
}
As other users have commented, your program is susceptible to many other issues depending on the string inputed. The example I have posted assumes that anything that is not a space is a letter and if you find at least one letter, than that's a word. Instead of boolean values you could use a counter to make sure that the word is at least a certain length. You could also check to see that it is not a number or symbol by either writing your own regex function or using an existing one. As others have said there is a lot more you can do with this program, but I've provided an example to point you in the right direction.

Answer 2

You are counting the amount of non-words, but you should be counting the amount of words.
If a word is defined as a sequence of one or more letters, your code might go as:
for every character in the string
if the character is part of a word ( "the car's wheel" is three words )
increase the word count
while the character is part of a word, increment your pointer

Answer 3

One improvement would be to handle lines that contain multiple spaces between words or tabs, while still considering a simple return '\n' as a word. Using getline provides a number of advantages including providing the number of characters read. Here is an example of the approach:
Edit logic simplified:
#include <stdio.h>
int main (void) {
char *line = NULL; /* pointer to use with getline () */
char *p = NULL; /* pointer to parse getline return */
ssize_t read = 0;
size_t n = 0;
int spaces = 0; /* counter for spaces and newlines */
int total = 0; /* counter for total words read */
printf ("\nEnter a line of text (or ctrl+d to quit)\n\n");
while (printf (" input: ") && (read = getline (&line, &n, stdin)) != -1) {
spaces = 0;
p = line;
if (read > 1) { /* read = 1 covers '\n' case (blank line with [enter]) */
while (*p) { /* for each character in line */
if (*p == '\t' || *p == ' ') { /* if space, */
while (*p == '\t' || *p == ' ') /* read all spaces */
p++;
spaces += 1; /* consider sequence of spaces 1 */
} else
p++; /* if not space, increment pointer */
}
}
total += spaces + 1; /* words in line = spaces + 1 */
printf (" chars read: %2zd, spaces: %2d total: %3d line: %s\n",
read, spaces, total, (read > 1) ? line : "[enter]\n");
}
printf ("\n\n Total words read: %d\n\n", total);
return 0;
}
output:
Enter a line of text (or ctrl+d to quit)
input: my
chars read: 3, spaces: 0 total: 1 line: my
input: dog has
chars read: 8, spaces: 1 total: 3 line: dog has
input: fleas and ticks
chars read: 17, spaces: 2 total: 6 line: fleas and ticks
input:
chars read: 1, spaces: 0 total: 7 line: [enter]
input:
chars read: 1, spaces: 0 total: 8 line: [enter]
input: total_words 10
chars read: 17, spaces: 1 total: 10 line: total_words 10
input:
Total words read: 10

Answer 4

//input should be alphanumeric sentences only
#include <bits/stdc++.h>
using namespace std;
int main()
{
freopen("count_words_input.txt","r",stdin); // input file
char c;
long long i,wcount=0,f=0;
i=0;
while(scanf("%c",&c) == 1)
{
if(c == ' ' || c == '\n' || c == '\t' || c == '.')
f=0;
else if(f == 0)
{
wcount++;
f=1;
}
}
printf("%lld\n",wcount);
return 0;
}