#include<stdio.h>

int main(){
	int whiteA,blackA,whiteB,blackB,AtoB,BtoA;
	scanf("%d%d%d%d%d%d",&whiteA,&blackA,&whiteB,&blackB,&AtoB,&BtoA);
	
	int white,black;
	if(AtoB >= blackA){
		black = blackA;
		white = AtoB - blackA;
	}else{
		black = blackA - AtoB;
		white = 0;
	}
	blackA -= black;
	whiteA -= white;
	blackB += black;
	whiteB += white;
	
	if(BtoA >= whiteB){
		black = BtoA - whiteB;
		white = whiteB;
	}else{
		black = 0;
		white = whiteB - BtoA;
	}
	
	blackA += black;
	whiteA += white;
	blackB -= black;
	whiteB -= white;
	
	printf("%d",whiteA);
}