Tontti

#include <iostream>
#include <algorithm>
#include <queue>
#include <stack>
#include <string>
#define INF 999999999
#define ll long long
using namespace std;

int main()
{
    int n, m, t;
    cin>>n>>m>>t;

    char c[n][m];
    int v[n][m][2];

    for (int y = 0; y < n; y++) {
        for (int x = 0; x < m; x++) {
            cin>>c[y][x];
            v[y][x][0] = 0;
            if (x > 0) v[y][x][0] = v[y][x - 1][0];
            if (c[y][x] == '*') v[y][x][0]++;
            v[y][x][1] = v[y][x][0];
            if (y > 0) v[y][x][1] += v[y - 1][x][1];
        }
    }
    int ans = 0;
    for (int y = 0; y < n; y++) {
        for (int x = 0; x < m; x++) {
            int i = 0;
            while (x + i < m && y + i < n) {
                int w = v[y+i][x+i][1];
                if (x > 0 && y > 0) w += v[y-1][x-1][1];
                if (x > 0) w -= v[y+i][x-1][1];
                if (y > 0) w -= v[y-1][x+i][1];
                if (w == t) ans++;
                else if (w > t) break;
                i++;
            }
        }
    }

    cout<<ans<<endl;

    return 0;
}

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