7.12.6

7.12.6

include <stdio.h>

int main(void)
{
char ch;
char prechar;
int frequency = 0;

while ((ch = getchar()) != '#')
{
if (ch == 'e')
prechar = 'e';
if ((ch == 'i') && (prechar == 'e'))
{
++frequency;
prechar = '\0'; // 字符赋空
}
}
printf("共有%d个ei\n", frequency);

return 0;
}