C++实现输入一段多行的文字，以空行结束，统计每个字母出现的个数（字母不区分大小写）

#include
#include
#include

#define MAX_NUMBER_LEN 11

enum STATE
{
ST_LINE,
ST_END,
};

int counta()
{
int count[26] = {0};
FILE *fp = stdin;
int ch;
enum STATE st = ST_END;
do
{
ch = fgetc(fp);
switch(st)
{
case ST_LINE:
if( ch=='\n' )
{
st = ST_END;
}
else
{
if( isalpha(ch) )
{
int c = tolower(ch);
count[c-'a']++;
}
}
break;
case ST_END:
if( ch=='\n' || ch==EOF )
{
ch = EOF;
}
else
{
st = ST_LINE;
if( isalpha(ch) )
{
int c = tolower(ch);
count[c-'a']++;
}
}
break;
}
}
while(ch!=EOF);

int i;
for(i=0; i<26; i++)
printf("%d ", count[i]);

printf("\n");

return 0;
}

int main(int argc, char *argv[])
{
counta();

return 0;
}