The key thing here is to find the three "F"s in the long words but not to miss the three "F"s in the word "of," which also appears three times. You might miss it if you read the sentence too quickly.

Alternatively,

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2

string = "FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF YEARS"
print string.count("F")

Copy the text into a word processing program and then use the search function with Ctrl-F for the letter "f". A good program will tell you the number of occurrences.

Ctrl + F then find F. Count the highlighted letters. Problem solved

PHP:

<?PHP

$string = "FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF YEARS...";

echo substr_count($string, "F");

?>

include<string.h>

int main() { int b,c=0; char a[]="FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF YEARS"; for(b=0;b<strlen(a);b++) { if(a[b]=='F') c=c+1; printf("%d\n",c); }

return 0;

}

since everyone writes a code in his preferred language, here is my C++ code :D :

string s = "FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF YEARS...";

int numb = 0;

for ( int i=0; i<s.size(); i++)
    if (s[i] == 'F')
        numb++;
cout << "Number of F: " << numb;

cout << endl;
return 0;

python code for the problem

given = "FINISHED FILES ARE THE RESULT OF YEARS OF             SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF         YEARS..."
count = 0
for i in given:
    if i == 'F':
        count = count + 1

print count

In a Python interactive window, such as PythonWin:

>>> "FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF YEARS...".count('F')

6

(I wouldn't trust myself to count anything myself.)

In PYTHON:

1. z = "FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF YEARS..."
2. x = z.count('F')
3. print x