#include<stdio.h>
#include<stdlib.h>
 int main() {
 int witdrw_amnt;
 float bal_amnt; 
scanf("%d",&witdrw_amnt);
 scanf("%f",&bal_amnt);
 if((witdrw_amnt>0&&witdrw_amnt<=2000)&& (bal_amnt>0&&bal_amnt<=2000)) {
	 if(witdrw_amnt%5==0) {
		 if(witdrw_amnt<bal_amnt) {
 		bal_amnt=bal_amnt-(witdrw_amnt+0.5); 
		printf("%.2f",bal_amnt); 
		} else {
			 printf("%.2f",bal_amnt); exit(0);
			 }
		 } else printf("%.2f",bal_amnt); }
		 return 0;
 } 

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MTAwMAoxMDAw

1000
1000