#include <stdio.h>

int main() 
{
    char arr[1001] = {0};
    int count = 0;
    scanf("%s",arr);
    for(int i = 0 ; arr[i] != '\0' ; i++ )
    {
        if(arr[i]=='o')count++;
    }
    printf("%d", count);
    return 0;    
}