Thread: Question sorting character arrays: C programming

I was just wondering why my code isn't working as it should, I will sort well for the FIRST letter, but will not keep checking to sort names in TRUE ALPHABETICAL order. Here is my function that I made to do this sorting:

for(pass = 0; pass < CLASS-1; pass++)
{
for(i = 0; i < CLASS-1; i++)
{
letterOne = students[i].lastName[0];
letterTwo = students[i+1].lastName[0];

if(letterOne > letterTwo)
{
for(k = 0; k < LAST_NAME; k++)
{
lastNameTempSpace[k] = students[i].lastName[k];
firstNameTempSpace[k] = students[i].firstName[k];
}

for(k = 0; k < LAST_NAME; k++)
{
students[i].lastName[k] = students[i+1].lastName[k];
students[i].firstName[k] = students[i+1].firstName[k];
}

for(k = 0; k < LAST_NAME; k++)
{
students[i+1].lastName[k] = lastNameTempSpace[k];
students[i+1].firstName[k] = firstNameTempSpace[k];
}
}

while(letterOne == letterTwo)
{
while(letterOne != ' ' && letterTwo != ' ')
{
l++;

letterOne = students[i].lastName[l+1];
letterTwo = students[i+1].lastName[l+1];

if(letterOne > letterTwo)
{
for(k = 0; k < LAST_NAME; k++)
{
lastNameTempSpace[k] = students[i].lastName[k];
firstNameTempSpace[k] = students[i].firstName[k];
}

for(k = 0; k < LAST_NAME; k++)
{
students[i].lastName[k] = students[i+1].lastName[k];
students[i].firstName[k] = students[i+1].firstName[k];
}

for(k = 0; k < LAST_NAME; k++)
{
students[i+1].lastName[k] = lastNameTempSpace[k];
students[i+1].firstName[k] = firstNameTempSpace[k];
}
if(letterOne == letterTwo)
{
letterOne = students[i].lastName[l];
letterTwo = students[i+1].lastName[l];
}
}
}
}
}
}

pointers? I'm not there yet, Im just trying to really get this done using arrays and structs without any pointers...or any other function i read: strcmp...what does that do? compares both strings, but then what? where do i go from there?