C. 打印出来的不对，目前还没搞清楚原因

Question

这是我的代码:

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

void splitString(char s[]) {

    char firstHalf[100] = { 0 };
    char secndHalf[100] = { 0 };

    for (int i = 0; i < strlen(s) / 2; i++){
        firstHalf[i] = s[i];
    }

    for (int i = strlen(s) /2; i < strlen(s); i++){
        secndHalf[i - strlen(s) / 2] = s[i];
    }

    printf("The string split in two is '%s, - %s' \n", firstHalf, secndHalf);
}

void upperCase(char s[]){

    //String in upper case
    for (size_t i = 0; i < strlen(s); i++)
    s[i] = toupper(s[i]);

        printf("The string in uppercase is '%s'", s);
}

void lowerCase(char s[]){

    //String in lower case
    for (size_t i = 0; i < strlen(s); i++)
        s[i] = tolower(s[i]);

        printf("The string in lowercase is '%s'", s);
}

int main() {

    char s[200];
    char splitS[200];

    printf("Type a string: ", sizeof( s));

    if (fgets(s, sizeof(s), stdin) != 0){
        printf("The string is '%s'", s);
    }

    strcpy(splitS, s);

    upperCase(s);
    lowerCase(s);
    splitString(splitS);

    return 0;
}

正确的打印方式应该是这样的:

The string is 'Hello world'

The string in uppercase is 'HELLO WORLD'

The string in lowercase is 'hello world'

The string split in two is 'Hello, - world'

但是它打印成这样:

The string is 'Hello world

'The string in uppercase is 'HELLO WORLD

'The string in lowercase is 'hello world

'The string split in two is 'Hello , - world

'

Answer 1

您需要阅读 documentation for fgets() (我的重点):

fgets() reads in at most one less than size characters from stream and stores them into the buffer pointed to by s. Reading stops after an EOF or a newline. If a newline is read, it is stored into the buffer. A terminating null byte ('\0') is stored after the last character in the buffer.

由于您输入的这些行末尾有换行符，因此您需要在代码中删除它们。