#include<stdio.h>

int main(void){
  int i;
  char C;
  int n = 0, max = 0;
  for(i = 0; i < 14; i++){
    scanf("%c", &C);
    if(C == 'o'){
      n++;
      if(max < n) max = n;
    }
    else n = 0;
  }
  printf("%d\n", max);
  return 0;
}