求大佬[face]emoji:054.png[/face]在努力敲代码中，但是是新手很多语句都不规范

求大佬[face]emoji:054.png[/face]在努力敲代码中，但是是新手很多语句都不规范，思路也不是很清晰[face]emoji:002.png[/face]

用C语言写了。

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

int main()
{
    int n, l;
    char s[101];
    char *p, *m, *q;

    printf("Please enter the length N: \n");
    scanf("%d", &n);
    
    if (n <= 0)
    {
        printf("Length must be positive.\n");
        return -1;
    }
    else if (n %2 == 1)
    {
        printf("Length must be even number.\n");
        return -1;
    }
    
    printf("Please enter the string S (max 100 characters): ");
    scanf("%s", s);

    l = strlen(s);
    if (l != n)
    {
        printf("String length %d is not equal to %d\n", l, n);
        return -1;
    }
    
    p = s;
    m = s + n / 2;
    q = m;
    while (p < m)
    {
        if (*p++ != *q++)
        {
            printf("No\n");
            return 0;
        }
    }
    printf("Yes\n");
    return 0;
}

// Output
Please enter the length N:                                                                                                                                                         
6                                                                                                                                                                                  
Please enter the string S (max 100 characters): abcabc                                                                                                                             
Yes


Please enter the length N:                                                                                                                                                         
6                                                                                                                                                                                  
Please enter the string S (max 100 characters): abcabd                                                                                                                             
No 

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什么编程语言呀？