Tontti

h, w, n = [int(i) for i in raw_input().split()]
ps = []
for y in range(h):
    q = raw_input()
    for x in range(w):
        if q[x] == "*":
            ps.append([x,y])

if n==0:
    print 0
else:
    r = 0
    for x in range(w):
        for y in range(h):
            for s in range(int(n**0.5), min(w-x+1, h-y+1)):
                if len([1 for p in ps if x<=p[0]<x+s and y<=p[1]<y+s]) == n:
                    r+=1
    print r
"""

4 5 3
.....
.*...
...*.
..*.*


4 6 3
..**..
**....
*...*.
..*...


"""

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: TIME LIMIT EXCEEDED

Test 7

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 8

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 9

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 10

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 11

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 12

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 13

Group: 3

Verdict: RUNTIME ERROR

Test 14

Group: 3

Verdict: RUNTIME ERROR

Test 15

Group: 3

Verdict: RUNTIME ERROR