I'm having a bit of trouble reversing a string. Here's a code snippet of how I'm currently trying to do it:
index_s1 = strlen(num_s1);
for (index_s2 = 0; index_s2 <= strlen(num_s1); index_s2++){
num_s2[index_s2] = num_s1[index_s1];
index_s1--;
}