#include <stdio.h>
#include <string.h>
int main(void)
{
int n;
int count;
char c;
scanf("%d%*c", &n);
while (n--)
count = 0;
while ((c = getchar()) != '\n')
if (c < 0)
count++;
}
printf("%d\n", count / 2);
return 0;