48.找出字符串中出现频率最高的字母

#include<stdio.h>
#include<string.h>
#include<ctype.h>

void fun(char *s)
{
int k[26] ={ 0 }, n, i, max = 0;
char ch;
while (*s)
{
if (isalpha(*s))
{
ch = tolower(*s);
n = ch - 'a';
k
+= 1;
}
s++;
if (max < k
)
max = k
;

}
printf("\nAfter count:\n");
for (i = 0;i < 26;i++)
if (k[i] == max)
printf("\nletter\'%c\':%dtimes\n", i + 'a', k[i]);
}

int main()
{
char s[81];
printf("\nEnter a string:\n\n");
gets(s);
fun(s);
getchar();
return 0;
}