Question

You have x no. Of 5 rupee coins and y no. Of 1 rupee coins. You want to purchase an item for amount z. The shopkeeper wants you to provide exact change. You want to pay using minimum number of coins. How many 5 rupee coins and 1 rupee coins will you use? If exact change is not possible then display -1.

Answer 1

$\huge\red{Answer}$

// A program in c language.

#include <stdio.h>

main()

{

int z, x, y;

scanf("%d %d %d",&z,&x,&y);

if (z > 5 * x + y) {

print("error: cost more than value of coins.\n");

return(-1);

}

int a,b,c,d;

a = z/5; b = z%5;

if (x <= a) c = x;

else c = a;

d = 5 * c + y - z ;

if ( d < 0 ) {

printf ("not possible to pay exactly. \n");

return(-1);

}

printf ("number of coins of denom 5: %d \n", c);

printf ("number of coins of denom 1: %d\n", d);

return (0);

}

// done.

HOPE IT HELPS YOU ☺ !!

Answer 2

Answer: python program

def make_amount(rupees_to_make,no_of_five,no_of_one):

  remaining_fives = no_of_five

  remaining_ones = no_of_one

  five_needed = rupees_to_make // 5 # number of fives needed

  one_needed = rupees_to_make - 5*five_needed

  if five_needed > remaining_fives: # If we need more fives than we have

     one_needed += 5 * (five_needed - remaining_fives) # Then we need more ones

     remaining_fives = 0 # and we use all our fives

  else:

      remaining_fives -= five_needed # we have enough fives so use them

  if one_needed > remaining_ones:

      print(-1)

      return # We don't have enough ones

  else:

      remaining_ones -= one_needed # remove the used ones

  print("No. of Five needed :", no_of_five- remaining_fives)

  print("No. of One needed  :", no_of_one- remaining_ones)

make_amount(16,1,15)