#include <stdio.h>

int main(void) {
	
double yearlyDeposit = 0;
int noError = 0;
while(noError == 0) {
    int errorCheck = scanf("%lf", &yearlyDeposit);
    if(errorCheck == 0) {
        printf("Invalid input, please try again\n");
        scanf("%*[^\n]\n");
    } else {
        noError = 1;
    }
}
printf("%f\n", yearlyDeposit);

	return 0;
}