prosit7

#include <stdio.h>

int i;

// coins & bills of the monetary sys
const int COINS[] = {500, 400, 100, 50, 40, 10, 5, 4, 1};

// ten's of aviable in sys *10 to have integers
const int TENS_COINS[] = {5, 4, 1};

float treasury;

// coeffs of the COINS in the order of COINS[] array
unsigned int stock_of_coins[] = {0, 0, 2, 10, 10, 10, 10, 10, 10};
unsigned int stock_of_tens[] = {20, 20, 20};


void change_calculation(int v, int state) {

    int c;
    float tens;

    while(v != 0) {

        for (i = 0 ; i<state ; i++) {

            if(v >= COINS[i] && state == 9) {
                //calcul
                c = v / COINS[i];
                v = v % COINS[i];

                //removing from the stock
                stock_of_coins[i] -= c;

                //displaying
                printf("%hd times %hd$ coin\n", c, COINS[i]);
            }
            if(v >= TENS_COINS[i] && state == 3) {
                //calcul
                c = v / TENS_COINS[i];
                v = v % TENS_COINS[i];

                //removing from the stock
                stock_of_tens[i] = stock_of_tens[i] - c;

                //displaying
                tens = TENS_COINS[i]*0.1;
                printf("%hd times %.1f$ coin\n", c, tens);
            }
        }
    }
}


void display_stock(int *array_stock, const int *array_coins, int state){

    for (i = 0 ; i < state ; i++){

        if (state == 9) {
            printf("%hd times %hd$ coin\n", array_stock[i], array_coins[i]);
        }

        if (state == 3) {
            float tens = array_coins[i]*0.1;
            printf("%hd times %.1f$ coin\n", array_stock[i], tens);
        }
    }
}

float calcul_treasury() {

    float _treasury;

    for (i = 0 ; i < 9 ; i++) {
        _treasury += COINS[i]*stock_of_coins[i];
    }

    for (i = 0 ; i < 3 ; i++) {
        _treasury += TENS_COINS[i]*stock_of_tens[i]*0.1;
    }

    return _treasury;
}


float moneyback_calculation(float a, float b) {
    return (b-a);
}


int get_int_part(float in) {
    int out = (int)in;
    return out;
}


int get_dec_part(float in) {
    in -= (int)in;
    in *= 10;
    int out = (int)in;
    return out;
}


int main(void) {

    //price variables
    float amount_tobepaid = 0;

    //money input variables
    float amount_received_instant = 0.0;
    float amount_received = 0.0;

    float moneyback = 0.0;
    int moneyback_int = 0;
    int moneyback_dec = 0;


    // enter the amount to be paid
    printf("Enter the amount to be paid : ");
    scanf("%f", &amount_tobepaid);


    // enter the amount received
    while((int)(amount_tobepaid*10) > (int)(amount_received*10)) {
        printf("Enter your payment : ");
        scanf("%f", &amount_received_instant);
        amount_received = amount_received + amount_received_instant;
    }


    // calculate the money back
    moneyback = moneyback_calculation(amount_tobepaid, amount_received);
    printf("Money back : %.1f$\n", moneyback);

    // separating the float money back into 2 int
    moneyback_int = get_int_part(moneyback);
    moneyback_dec = get_dec_part(moneyback);
    //printf("int %hd\ndec %hd\n\n", moneyback_int, moneyback_dec);

    //get the details of the moneyback
    printf("Details of the moneyback :\n");
    change_calculation(moneyback_int, 9);
    change_calculation(moneyback_dec, 3);


    //display stcock COINS
    printf("\nIn stock :\n");
    display_stock(&stock_of_coins[0], &COINS[0], 9);
    display_stock(&stock_of_tens[0], &TENS_COINS[0], 3);


    //calcul treasury
    treasury = calcul_treasury();
    treasury += amount_tobepaid;
    //display treasury
    printf("\nTreasury : %.1f$\n", treasury);


    return 0;
}