/**
* Created by Frans on 5.10.2015.
*/
public class Tontti{
static int height;
static int width;
static int[][] kenttaSumma;
static int wantedTrees;
//static long runAmount;
public static void main(String[] args){
/*//todo
int futureWidth = 500;
int futureHeight = 500;
int futurewantedTrees = (int) (Math.random() * futureHeight);
height = futureHeight;
width = futureWidth;
wantedTrees = futurewantedTrees;
kentta = new byte[width+1][height+1];
kenttaSumma = new int[width+1][height+1];
String[] lines = new String[height+1];
for (int y=1; y<=height; y++) {
//todo
lines[y] = "";
for (int x2=1; x2<=width; x2++){
if (Math.random() > 0.3){
lines[y] = lines[y] + ".";
}else {
lines[y] = lines[y] + "*";
}
}
}*/
IO io = new IO();
height = io.nextInt();
width = io.nextInt();
wantedTrees = io.nextInt();
//long aika = System.nanoTime();
kenttaSumma = new int[width+1][height+1];
int foundArea = 0;
int minSize = (int) (Math.sqrt(wantedTrees) + 0.99);
//calculate trees and save it in to array and summed area table
for (int y=1; y<=height; y++) {
String line = io.next();
//String line = lines[y];
int sumRow = 0;
for (int x=1; x<=width; x++){
if (line.charAt(x-1) == '*'){
sumRow ++;
}
kenttaSumma[x][y] = sumRow + kenttaSumma[x][y-1];
int maxSize = min(x, y);
if (x==4 && y==3){
x=4;
}
if(maxSize >= minSize){
foundArea += countAreasB(maxSize,minSize,x,y,0);
}
}
}
io.println(foundArea);
/*aika = (System.nanoTime()-aika)/1000000;
io.println("---");
io.println("Time: " + aika);
io.println("Loops: " + runAmount);
*/
io.close();
}
//rekursiivinen binaarihaku
// x2 = x -1
// y2 = y -1
private static int countAreasB(int maxSize,int minSize, int x, int y, int prevSize){
int areasFound = 0;
int tSize = (int) ((maxSize + minSize)/2.0 + 0.99);
//lopetaan kun sama on jo katsottu
if (prevSize != tSize){
prevSize = tSize;
int sum = kenttaSumma[x][y]+kenttaSumma[x-tSize][y-tSize]-kenttaSumma[x][y-tSize]-kenttaSumma[x-tSize][y];
if(sum > wantedTrees){
areasFound += countAreasB(tSize, minSize, x, y, prevSize);
}else if (sum < wantedTrees){
areasFound += countAreasB(maxSize, tSize, x, y, prevSize);
}else {
//molemmat suunnat ovat mahdollisia --> kokeillaan kaikki lähellä olevat
areasFound ++;
areasFound += countAreasL(tSize+1, maxSize, x, y, 1);
areasFound += countAreasL(tSize-1, minSize, x, y, -1);
}
}
return areasFound;
}
//suoraviivainen haku
// x2 = x-1
// y2 = y-1
private static int countAreasL(int startSize,int endSize, int x, int y, int direction){
int areasFound = 0;
for (int tSize=startSize; direction*tSize<=endSize*direction; tSize=tSize+direction){
int sum = kenttaSumma[x][y]+kenttaSumma[x-tSize][y-tSize]-kenttaSumma[x][y-tSize]-kenttaSumma[x-tSize][y];
if (sum == wantedTrees){
areasFound ++;
}else{
break;
}
}
return areasFound;
}
//just for lulz
private static int max(final int a, final int b){
return (a>b)?a:b;
}
private static int min(final int a, final int b){
return (a<b)?a:b;
}
}