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][height];
        kenttaSumma = new int[width][height];
 
 
        //calculate trees and save it in to array
        for (int y=0; y<height; y++) {
            String line = io.next();
            int tmpRivi = 0;
            for (int x=0; x<width; x++){
                if (line.charAt(x) == '*'){
                    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=0; y<height-(minSize-1); y++){
            for (int x=0; x<width-(minSize-1); x++){
                int testW = optimizeW;
 
                testW = Math.min(Math.min(testW, height-y), width-x);
                int amount = CountTree2(testW, x, y);
 
                //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
        int amount = kenttaSumma[x+testW][y+testW];
        if (x > 0){
            amount -= kenttaSumma[x-1][y+testW];
        }
        if (y > 0){
            amount -= kenttaSumma[x+testW][y-1];
        }
        if (x > 0 && y > 0){
            amount += kenttaSumma[x-1][y-1];
        }
        return amount;
    }
 
    private static int CountTree(int testW, int x, int y) {
        int squareTreeAmount = 0;
        //System.out.println("----" + x + "------" + y);
        for (int y2 = y; y2 < y + testW; y2++) {
            //String debug = "";
            for (int x2 = x; x2 < x + testW; x2++) {
                squareTreeAmount += kentta[x2][y2];
                /*if (kentta[x2][y2] == 1){
                    debug = debug + "*";
                }else{
                    debug = debug + ".";
                }*/
            }
            //System.out.println(debug);
        }
        runAmount ++;
        return squareTreeAmount;
    }
 
    private static int DecreaseArea(int testW, int x, int y){
        int foundArea = 0;
        testW --;
        while(testW >= minSize){
            int squareTreeAmount = CountTree2(testW, x, y);
            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 && testW + x <= width){
            int squareTreeAmount = CountTree2(testW, x, y);
            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