I found this question at codejam. You can find the problem here. So lets get onto the problem.

Problem

You receive a credit C at a local store and would like to buy two items. You first walk through the store and create a list L of all available items. From this list you would like to buy two items that add up to the entire value of the credit. The solution you provide will consist of the two integers indicating the positions of the items in your list (smaller number first).

Input

The first line of input gives the number of cases, N. N test cases follow. For each test case there will be:

One line containing the value C, the amount of credit you have at the store.

One line containing the value I, the number of items in the store.

One line containing a space separated list of I integers. Each integer P indicates the price of an item in the store.

Each test case will have exactly one solution.Output

For each test case, output one line containing “Case #x: ” followed by the indices of the two items whose price adds up to the store credit. The lower index should be output first.

Limits

5 ≤ C ≤ 1000

1 ≤ P ≤ 1000Small dataset

N = 10

3 ≤ I ≤ 100Large dataset

N = 50

3 ≤ I ≤ 2000

Input:

1 2 3 4 5 6 7 8 9 10 |
3 100 3 5 75 25 200 7 150 24 79 50 88 345 3 8 8 2 1 9 4 4 56 90 3 |

Output:

1 2 3 |
Case #1: 2 3 Case #2: 1 4 Case #3: 4 5 |

My Program:

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 |
import java.io.BufferedReader; import java.io.DataInputStream; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStreamReader; import java.util.ArrayList; public class StoreCredit { /** * @param args */ public static Object[] getItems(int items[], int total) { ArrayList selectedItems = new ArrayList(); int index = 0; for (int i = 0; i<items.length; i++) { for (int j = i+1; j < items.length; j++) { if (items[i] + items[j] == total) { selectedItems.add(index, i); selectedItems.add(index+1,j); } } } return selectedItems.toArray(); } public static int[] convertStringToInt(String array[]) { int intArray[] = new int[array.length]; for (int i = 0; i < array.length; i++) intArray[i] = Integer.parseInt(array[i]); return intArray; } public static void main(String[] args) throws IOException { FileInputStream fis = new FileInputStream("StoreCreditLarge.in"); DataInputStream in = new DataInputStream(fis); BufferedReader br = new BufferedReader(new InputStreamReader(in)); String N = br.readLine(); String line = null; int caseNo = 1; while((line = br.readLine()) != null ) { int credits = Integer.parseInt(line); int totalItems = Integer.parseInt(br.readLine()); String strItems[] = br.readLine().split(" "); int Items[] = convertStringToInt(strItems); //System.out.println("Credits: "+credits+" total= "+totalItems+"ItemsLength= "+Items.length); Object selectedItems[] = getItems(Items, credits); //System.out.println(selectedItems.length); System.out.println("Case #"+caseNo+":"+printArray(selectedItems)); caseNo++; } } public static String printArray(Object[] selectedItems) { // TODO Auto-generated method stub String result = ""; for (int i=0; i<selectedItems.length; i++) result = result +" "+((int)selectedItems[i]+1); return result; } } |

Output:

#### Vlad

#### Latest posts by Vlad (see all)

- Code jam “Tic-Tac-Toe-Tomek” solution in java - April 19, 2013
- Code jam “Minimum Scalar product” solution in java - March 18, 2013
- Code jam Store Credit solution in java - March 10, 2013