the spy life, what is the error in the code?

Question

/*In a test case it should return "tacos" but my code return "∆tacos"*/
#include <stdio.h>
#include <string.h>
#include <ctype.h>
int main() {
char a[50],b[50],rev[50];
int c,aux;
gets(a);
for(int i=0;i<=strlen(a); i++){
if(isalpha(a[i])||a[i]==' '){b[c]=a[i];c++;}
}
aux=strlen(b);
for (int j=0;j<=strlen(b); j++){
rev[j]=b[aux-1];
aux--;
}
puts(rev);
return 0;
}

Answer 1

you must first initialize 'c' to zero, and mark the end of the string with null char (zero char code) to get the right length

https://code.sololearn.com/cTZdnQ5UWZlM/?ref=app

Answer 2

https://code.sololearn.com/cA4vuwo47XPZ/?ref=app

• A string must be terminated by NULL (\0)
• fgets should be used instead of gets
• you didn't intialized c
• i and j should be declared outside for loop