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POWrong results while calculate sum
 

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  1. POWrong results while calculate sum
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    <p>I am writing a shop simulator for homework. A user inputs items for sale (set name and price) and then the user buys these items - entering ID (1-5) and count. And then - price counting (my problem). </p> <p>It must be done simply, but I can't find what is wrong. The final price has strange values, and I can't understand why.</p> <p>In this code I added some lines of "debugger" code, that show intermediate numbers - for best understanding of process.</p> <pre><code>import java.util.Scanner; public class HomeWork3Shop { private static Scanner inputAdmin; public static void main(String[] args) { String[] items = new String[6]; int[] price = new int[6]; // The administrator adds the information about the products System.out.println("Administrator: add five items - name and price: "); for (int i = 1; i &lt; 6; i++) { // if int = 0 -- will be "item 0: xxx" - not good System.out.print(" item " + i + ": "); inputAdmin = new Scanner(System.in); items[i] = inputAdmin.next(); System.out.print("Price " + i + ": "); inputAdmin = new Scanner(System.in); price[i] = inputAdmin.nextInt(); } int[][] buyList = new int[2][6]; String yn = null; System.out.print("\nAdded. Plese buy - enter ID of item (1-5): "); int i = 1; for (int i2 = 0; i2 &lt; 5; i2++) { // Enter ID of item: Scanner inputShoper = new Scanner(System.in); buyList[0][i] = inputShoper.nextInt(); // Insert ID of item to the array - for next price count System.out.print("How much? (Enter a number): "); buyList[1][i++] = inputShoper.nextInt(); System.out.print("\nIn bag. Want buy more? [y/n] "); Scanner YN = new Scanner(System.in); yn = YN.next(); if (yn.equals("n")) { break; } System.out.print("Enter ID of next item to buy: "); } for (int row = 0; row &lt; buyList.length; row++) { // paint a table for (int col = 0; col &lt; buyList[row].length; col++) { System.out.print(buyList[row][col] + "\t"); } System.out.println(); } for (int temp = 0; temp &lt; items.length; temp++) { System.out.print(" " + items[temp]); } for (int temp = 0; temp &lt; items.length; temp++) { System.out.print(" " + price[temp]); } // ----- price count int totalPrice = 0; int tempPrice = 0; for (i = 1; i &lt; buyList[0].length; i++) { tempPrice = buyList[1][i] * price[i]; System.out.print(" | " + tempPrice); totalPrice += buyList[1][i] * price[i]; System.out.println(totalPrice); // count * price } System.out.println("Your price is: " + totalPrice); // ----- black list ----- System.out.print("How much money you have? "); int cash = 0; Scanner Cash = new Scanner(System.in); cash = Cash.nextInt(); if (cash &lt; totalPrice) { System.out.println("You are in our Black List."); } else { System.out.println("Thank you for purchasing."); } } } </code></pre> <p>Output:</p> <blockquote> <pre><code> Administrator: add five items - name and price: item 1: Milk Price 1: 11 item 2: Broad Price 2: 22 item 3: Mouse Price 3: 33 item 4: Keyboard Price 4: 44 item 5: Monitor Price 5: 55 Added. Plese buy - enter ID of item (1-5): 1 How much? (Enter a number): 1 In bag. Want buy more? [y/n] y Enter ID of next item to buy: 2 How much? (Enter a number): 2 In bag. Want buy more? [y/n] y Enter ID of next item to buy: 5 How much? (Enter a number): 4 In bag. Want buy more? [y/n] n 0 1 2 5 0 0 0 1 2 4 0 0 null Milk Broad Mouse Keyboard Monitor 0 11 22 33 44 55 | 1111 | 4455 | 132187 | 0187 | 0187 Your price is: 187 </code></pre> </blockquote> <p>Final price - 187. But:</p> <p>(11*1) + (22*2) + (55*4) = 22 + 44 + 220 = 286.</p> <p>286 - must be, but this code get 187.</p> <p>Its calculate in this line of code:</p> <pre><code>totalPrice += buyList[1][i] * price[i]; </code></pre>
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    1. USVitaly Zdanevich
    1. USVitaly Zdanevich
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    1. This table or related slice is empty.
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      1. POWrong results while calculate sum
      1. This table or related slice is empty.
      1. VTDownMod
    2. VO
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      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
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      1. VTApproveEditSuggestion
    1. COdon't downvote without comment
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      1. POWrong results while calculate sum
      1. USArpit
    2. CODon't create a new `Scanner` all the time. What are the values you expect and what is output? Have you used step-by-step debugger?
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      1. POWrong results while calculate sum
      1. USNikolay Kuznetsov
    3. COOh, I don't know about "step-by-step debugger" - can you send link?
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      1. POWrong results while calculate sum
      1. USVitaly Zdanevich
 

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