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

char*mmap();

main(){
	int a=0,b=0,c;
	char*r=mmap(0l,1280l*1024,1,2,0,0l);
	while(*r++>=45);
	while(c=*r++){
		if(c<45){
			a+=b&1?1:-1;
		}
		b=c;
	}
	printf("%d",a<0?-a:a);
}