最大限度地减少购买对象的成本

给定“ T” ，代表一个人拥有的物品总数。 “ P”代表每件商品的价格， “ M”代表他购买“ N”件商品可获得的免费商品数量。任务是找到该人为获得T物品而必须支付的总金额。
例子：

Input: T = 13, P = 10, N = 3, M = 1 
Output: Amount = 100 
Explaination: 
Total number of fruit bottle a person has = 13 
Offer available is buy 3 get 1 free 
So, person has to buy 9 Fruit juice bottle to get 3 fruit juice bottle for free. 
Now, since the total number of the bottle is 13 so the person buys 1 bottle at P price.
The total amount the person has to pay = (9 + 1) * 10 i.e 100
Input: T = 12, P = 8, N = 2, M = 1 
Output: Amount = 64 
 

方法：

1. 首先，我们应该尝试获得尽可能多的免费物品，这样可以降低成本。
2. 将项目总数除以N和M之和，因为当我们购买至少N个项目时，我们得到M个免费项目。
3. 然后通过从项目总数中减去免费项目来计算您必须支付的项目总数
4. 最后，可以通过将一件商品的成本乘以一件商品的总数来计算价格。

下面是上述方法的实现：

C++

// C++ program of above approach
#include 
using namespace std;
 
// Function that will calculate the price
int totalPay(int totalItems, int priceOfOneItem,
             int N, int M)
{
    int freeItems = 0, actual = 0;
 
    // Calculate the number of items
    // we can get for free
    freeItems = totalItems / (N + M);
 
    // Calculate the number of items
    // we will have to pay the price for
    actual = totalItems - freeItems;
 
    // Calculate the price
    int amount = actual * priceOfOneItem;
 
    return amount;
}
 
// Driver code
int main()
{
    int T = 12, P = 8;
    int N = 2, M = 1;
 
    // Calling function
    cout << "Amount = "
         << totalPay(T, P, N, M);
 
    return 0;
}

Java

// Java implementation of the approach
class GFG
{
 
// Function that will calculate the price
static int totalPay(int totalItems,
                    int priceOfOneItem,
                    int N, int M)
{
    int freeItems = 0, actual = 0;
 
    // Calculate the number of items
    // we can get for free
    freeItems = totalItems / (N + M);
 
    // Calculate the number of items
    // we will have to pay the price for
    actual = totalItems - freeItems;
 
    // Calculate the price
    int amount = actual * priceOfOneItem;
 
    return amount;
}
 
// Driver code
public static void main(String[] args)
{
    int T = 12, P = 8;
    int N = 2, M = 1;
 
    // Calling function
    System.out.print("Amount = " +
                      totalPay(T, P, N, M));
}
}
 
// This code is contributed by 29AjayKumar

Python3

# Python3 program of above approach
 
# Function that will calculate the price
def totalPay(totalItems, priceOfOneItem, N, M):
    freeItems = 0
    actual = 0
 
    # Calculate the number of items
    # we can get for free
    freeItems = totalItems // (N + M)
 
    # Calculate the number of items
    # we will have to pay the price for
    actual = totalItems - freeItems
 
    # Calculate the price
    amount = actual * priceOfOneItem
 
    return amount
 
# Driver code
T = 12
P = 8
N = 2
M = 1
 
# Calling function
print("Amount = ", totalPay(T, P, N, M))
 
# This code is contributed by Mohit Kumar

C#

// C# implementation of the approach
using System;
class GFG
{
 
// Function that will calculate the price
static int totalPay(int totalItems,
                    int priceOfOneItem,
                    int N, int M)
{
    int freeItems = 0, actual = 0;
 
    // Calculate the number of items
    // we can get for free
    freeItems = totalItems / (N + M);
 
    // Calculate the number of items
    // we will have to pay the price for
    actual = totalItems - freeItems;
 
    // Calculate the price
    int amount = actual * priceOfOneItem;
 
    return amount;
}
 
// Driver code
public static void Main(String[] args)
{
    int T = 12, P = 8;
    int N = 2, M = 1;
 
    // Calling function
    Console.Write("Amount = " +
                   totalPay(T, P, N, M));
}
}
 
// This code is contributed by PrinciRaj1992

Javascript

 
// Javascript program of above approach
 
// Function that will calculate the price
function totalPay(totalItems, priceOfOneItem,
             N, M)
{
    var freeItems = 0, actual = 0;
 
    // Calculate the number of items
    // we can get for free
    freeItems = totalItems / (N + M);
 
    // Calculate the number of items
    // we will have to pay the price for
    actual = totalItems - freeItems;
 
    // Calculate the price
    var amount = actual * priceOfOneItem;
 
    return amount;
}
 
// Driver code
var T = 12, P = 8;
var N = 2, M = 1;
// Calling function
document.write( "Amount = "
     + totalPay(T, P, N, M));
 

输出：

Amount = 64