Alright, i tried Salem's idea, but it always comes out with 'L' as being the most used char even if there isn't an L in the string. I think it might have to do with turning the string to a char array so I can read each char seperately. I switched the L char to a different letter and it displayed that char. I also took the 'L' out, and typed "ttttt" and it said 'a' was the most common. So is it the strcpy() screwing it up?
Code:
char ReturnMostUsed(string* ptr){
char common;
int size = sizeof(ptr), count = 0;
char line[size+1];
int a=0,b=0,c=0,d=0,e=0,f=0,g=0,
h=0,i=0,j=0,k=0,l=0,m=0,n=0,
o=0,p=0,q=0,r=0,s=0,t=0,u=0,
v=0,w=0,x=0,y=0,z=0;
strcpy(line,(char*)ptr);
while(count <= size){
if(isalpha(line[count])){
if(line[count] == 'a')
a++;
// further down the code it goes through all the possible chars
// then finds which ever count is highest, then displays that char