#include <stdio.h>

void main(void) {
	int a,b,c,d;
	scanf("%d %d %d %d",&a,&b,&c,&d);
	int damagePoint = 0;
	if(a+b+c+d > c*3){
		damagePoint = a + b + c + d;
	}else{
		damagePoint = c*3;
	}
	printf("%d",damagePoint);
}