argvtac.c is a program that concatenates in reverse order all the arguments passed to it as command line arguments and prints to standard output the resulting string. The program has correct output, but leaks memory. Run valgrind in the your code-server IDE to find and correct the leak and submit the corrected code.

For example:

Test	Result
./argvtac	./argvtac
./argvtac	./argvtac
./argvtac mb	mb./argvtac

#include #include #include

/* return the length of a string * For example, * return 0 if s is \"\" * return 3 if s is \"abc\" */ unsigned long my_strlen(char *s) { unsigned long i = 0;

while (*s++) i++; return i; }

/* Concatnate two strings. * Dynamically allocate space for the result. * Return the address of the result. */ char *my_strcat(char *s1, char *s2) { char *r; unsigned long len1, len2, i;

len1 = my_strlen(s1); len2 = my_strlen(s2);

r = malloc(len1 + len2 + 1); assert (r != NULL);

// copy, using array notation for(i = 0; i r[i] = s1[i];

for(i = 0; i r[len1+i] = s2[i];

r[len1+len2] = 0; return r; }

/* * Concatenate command line arguments in reverse order * and print them to the standard output */ int main(int argc, char *argv[]) { int i; char *s;

// initialize s to be \"\" s = malloc(1); assert(s != NULL); *s = 0;

for(i = argc-1; i >= 0; i--) s = my_strcat(s, argv[i]);

printf(\"%s \", s);

return 0; }