ex11-3.c

#include <stdio.h>

int findCombi(int toHour) {
  int aHour = 300;   // 300 Hours
  int aPrice = 100;  // 100 JPY
  int bHour = 500;   // 500 Hours
  int bPrice = 180;  // 180 JPY

  int aNum = toHour / aHour;
  int bNum = toHour / bHour;
  int a, b;
  int allPrice = (toHour / aHour) * aPrice + (toHour / bHour) * bPrice;
  int ableTime = (toHour / aHour) * aHour + (toHour / bHour) * bHour;

  for (int i = aNum; i >= 0; i--) {
    for (int j = bNum; j >= 0; j--) {
      if (allPrice > i * aPrice + j * bPrice) {
        if (i * aHour + j * bHour >= toHour) {
          allPrice = i * aPrice + j * bPrice;
          a = i;
          b = j;
        }
      }
    }
  }

  printf("最安値は電池Aが%d本、電池Bが%d本、価格は%d円です\n", a, b, allPrice);

  return 0;
}

int main() {
  int allNum;
  printf("Input available time > ");
  scanf("%d", &allNum);
  findCombi(allNum);
  return 0;
}