#pragma GCC optimize("Ofast")
#pragma GCC target("avx2")

char*mmap();

#define wt(v) {int _z=v;do*--wp=_z%10+48;while(_z/=10);}

main(){
	char*rp=mmap(0l,1l<<20,1,2,0,0ll);

	int res=-1;
	for(int c;c=*(int*)rp++;){
		if(c=='niap'){
			goto end;
		}
		if((c&0xffffff)=='nop'){
			++res;
		}
	}
	res=-1;

	end:;
	char wbuf[64],*wp=wbuf+sizeof wbuf;
	if(res<1){
		*--wp='1';
		*--wp='-';
	}else{
		wt(res);
	}
	write(1,wp,wbuf+sizeof wbuf-wp);
	_exit(0);
}