Tontti

/**
 * Created by Frans on 5.10.2015.
 */
public class Tontti{

    static int height;
    static int width;
    static byte[][] kentta;
    static int[][] kenttaSumma;
    static int treeWanted;
    static int trees;
    static int minSize;
    static int runAmount;

    public static void main(String[] args){
        IO io = new IO();

        height = io.nextInt();
        width = io.nextInt();
        treeWanted = io.nextInt();
        trees = 0;

        kentta = new byte[width+1][height+1];
        kenttaSumma = new int[width+1][height+1];

        //calculate trees and save it in to array and summed area table
        for (int y=1; y<=height; y++) {
            String line = io.next();
            int tmpRivi = 0;
            for (int x=1; x<=width; x++){
                if (line.charAt(x-1) == '*'){
                    kentta[x][y] = 1;
                    tmpRivi ++;
                }else{
                    kentta[x][y] = 0;
                }
                kenttaSumma[x][y] = tmpRivi + kenttaSumma[x][Math.max(y-1,0)];
            }
            trees += tmpRivi;
        }



        minSize = (int) Math.ceil(Math.pow(treeWanted,0.5));

        //optimized test area
        double density = (double) trees/ (double) (width*height);
        int optimizeW = Math.max((int) Math.ceil(Math.pow((treeWanted / density), 0.5)), 2);

        int foundArea = 0;

        int direction =0;

        //-1, koska oikea reuna turha kayda
        for(int y=1; y<=height-(minSize-1); y++){
            for (int x=1; x<=width-(minSize-1); x++){
                int testW = optimizeW;

                int tmpX = x-1;
                int tmpY = y-1;

                testW = Math.min(Math.min(testW, height-tmpY), width-tmpX);
                int amount = kenttaSumma[tmpX+testW][tmpY+testW]+kenttaSumma[tmpX][tmpY]-kenttaSumma[tmpX][tmpY+testW]-kenttaSumma[tmpX+testW][tmpY];

                //haluttu maara
                if (amount == treeWanted){
                    foundArea ++;
                    foundArea += IncreaseArea(testW, x, y);
                    foundArea += DecreaseArea(testW, x, y);
                } else if (amount < treeWanted){
                    foundArea += IncreaseArea(testW, x, y);
                } else { //amount > treeWanted
                    foundArea += DecreaseArea(testW, x, y);
                }

            }
        }

        io.println(foundArea);
        io.close();

    }

    private static int CountTree2(int testW, int x, int y){
        testW --; //jos pituus 2, talloin sivu (2-1) pidempi
        return kenttaSumma[x+testW][y+testW] + kenttaSumma[x-1][y-1]-kenttaSumma[x-1][y+testW]- kenttaSumma[x+testW][y-1];
    }


    private static int DecreaseArea(int testW, int x, int y){
        int foundArea = 0;
        testW --;
        while(testW >= minSize){
            int tmpX = x-1;
            int tmpY = y-1;
            int squareTreeAmount = kenttaSumma[tmpX+testW][tmpY+testW]+kenttaSumma[tmpX][tmpY]-kenttaSumma[tmpX][tmpY+testW]-kenttaSumma[tmpX+testW][tmpY];
            if(squareTreeAmount == treeWanted){
                foundArea ++;
            }
            testW --;
        }
        return foundArea;
    }

    private static int IncreaseArea(int testW, int x, int y){
        int foundArea = 0;
        testW ++;
        while(testW + y <= height+1 && testW + x <= width+1){
            int tmpX = x-1;
            int tmpY = y-1;
            int squareTreeAmount = kenttaSumma[tmpX+testW][tmpY+testW]+kenttaSumma[tmpX][tmpY]-kenttaSumma[tmpX][tmpY+testW]-kenttaSumma[tmpX+testW][tmpY];
            if(squareTreeAmount == treeWanted){
                foundArea ++;
            }
            testW ++;
        }
        return foundArea;
    }


}

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 1

Verdict: ACCEPTED

Test 3

Group: 1

Verdict: ACCEPTED

Test 4

Group: 1

Verdict: ACCEPTED

Test 5

Group: 1

Verdict: ACCEPTED

Test 6

Group: 2

Verdict: ACCEPTED

Test 7

Group: 2

Verdict: ACCEPTED

Test 8

Group: 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: ACCEPTED

Test 10

Group: 2

Verdict: ACCEPTED

Test 11

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 12

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 13

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 14

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 15

Group: 3

Verdict: TIME LIMIT EXCEEDED