how to prevent print enter key (\n) being print in output area

Question

I have a problem with the print output, every time it prints "12" it enters down and I don't know what is the problem, i have tried print it separately but no luck (code below)

the question

A baseball player’s batting average is calculated as the number of hits divided by the official number of at-bats. In calculating official at-bats, walks, sacrifices, and occasions when hit by the pitch are not counted. Write a program that takes an input file containing player numbers and batting records. Trips to the plate are coded in the batting record as follows: H—hit, O—out, W—walk, S—sacrifice, and P—hit by pitch. The program should output for each player the input data followed by the batting average. (Hint: Each batting record is followed by a newline character.)

Sample input file:

12 HOOOWSHHOOHPWWHO

4 OSOHHHWWOHOHOOO

7 WPOHOOHWOHHOWOO

Corresponding output:

Player 12's record: HOOOWSHHOOHPWWHO

Player 12's batting average: 0.455

Player 4's record: OSOHHHWWOHOHOOO

Player 4's batting average: 0.417

Player 7's record: WPOHOOHWOHHOWOO

Player 7's batting average: 0.364

the code

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <math.h>
int main() {
    char str[1000];
    int count = 0;
    int count2 = 0;
    char ch = 'H';
    char ch2 = 'O';
    double top = 0;
    double bottom = 0;
    double avg;
    char PN[1000];

    printf("Enter player's number:");
    fgets(PN, sizeof(PN), stdin);

    printf("Enter a record: ");
    fgets(str, sizeof(str), stdin);

    for (int i = 0; str[i] != '\0'; ++i) { //counts H//
        if (ch == str[i])
            ++count;
        top = count;
    }

    for (int i = 0; str[i] != '\0'; ++i) { //counts O//
        if (ch2 == str[i])
            ++count2;
        bottom = count2;
    }

    avg = top / (top + bottom); // H / ( H + O ) //


    printf("Player %s's record: %s", PN, str);

    printf("Player %s's batting average: %.3lf", PN, avg);


    return 0;
}

my code's output

input
Enter player's number:12
Enter a record: HOOOWSHHOOHPWWHO

output
Player 12
's record: HOOOWSHHOOHPWWHO
Player 12
's batting average: 0.455

should be

Player 12's record: HOOOWSHHOOHPWWHO
Player 12's batting average: 0.455

Hint: `fgets(PN, sizeof(PN), stdin);` how much of the input does it read? (if you read from a file, that is.) — Sourav Ghosh, Nov 08 '21 at 06:48

score 1 · Accepted Answer · answered Nov 08 '21 at 06:52

1

fgets() reads and stores the trailing newline in the buffer. One way of getting rid of that is to use strcspn(), like

PN[strcspn(PN, "\n")] = 0;

answered Nov 08 '21 at 06:52

Sourav Ghosh

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thankyou so much for helping me but can you explain how ```strcspn()``` work? – newb Nov 08 '21 at 07:00
Please read the linked man page, please ask if you have trouble understanding any specific part. – Sourav Ghosh Nov 08 '21 at 07:08

absuu · Answer 2 · 2021-11-08T07:30:02.917

A Quick Solution: Add just one line of code to yours:

printf("Enter player's number:");

// ------------    note that <string.h> needs to be included
PN[strlen(PN)-1]='\0';   //   <------here
// ------------

fgets(PN, sizeof(PN), stdin);

More Information:

For function fgets, according to man7 's definitions:

The fgets() function shall read bytes from stream into the array pointed to by s until n-1 bytes are read, or a is read and transferred to s, or an end-of-file condition is encountered. A null byte shall be written immediately after the last byte read into the array

After fgets, the data is copied to PN buffer from stdio stream buffer using size sizeof(PN) (i.e 1000), the resulting PN will be like this:

{ '1' , '2' , '\n' , '\0' , '\0' , '\0' , ...... }

After that, when you are calling printf, some of characters of PN will be copied to STDOUT (i.e. shell), and they are something like this:

{ '1' , '2' , '\n' , '\0' }     // note that '\0' is just an terminator, and will not be displayed on screen.

, which includes one more character than we need, and that character is a newline character \n.

When you are calling printf("Player %s's record: %s", PN, str);, the newline character \n will be treated as a control character, which results in an effect of ENTER key, this is the reason why your program always enters down while printing "12".

thankyou too for helping me is it taking the length of the string then reducing it by 1? — newb, Nov 08 '21 at 07:05
yes exactly, I've also added some of more specific explanations here. And while this solution works just fine, there are many other effective solutions, such as @Sourav Ghosh 's suggestions. — absuu, Nov 08 '21 at 07:39

how to prevent print enter key (\n) being print in output area

2 Answers2