钉板上的正方形 参考代码

#include <bits/stdc++.h>
using namespace std;

typedef long long LL;
const int maxn = 200000 + 100;
struct Vector {
    int x, y;
    Vector() : x(0), y(0) {}
    Vector(int x, int y) : x(x), y(y) {}
};

Vector operator+(const Vector &a, const Vector &b) {
    return Vector(a.x + b.x, a.y + b.y);
}

int operator*(const Vector &a, const Vector &b) {
    return a.x * b.x + a.y * b.y;
}

Vector rotate90(const Vector &v) {
    return Vector(Vector(0, -1) * v, Vector(1, 0) * v);
}

int n = 10;
set<int> st;
string G[10] = {
    "1101011111",
    "1110011110",
    "1100101111",
    "1011011110",
    "1010111100",
    "1001010101",
    "1111111110",
    "0111111110",
    "0110101111",
    "1010010100"
};

bool judge(const Vector &p) {
    return p.x >= 0 && p.x < n && p.y >= 0 && p.y < n && G[p.x][p.y] == '1';
}

bool judge(int x1, int y1, int x2, int y2) {
    Vector v(x2 - x1, y2 - y1);
    v = rotate90(v);
    Vector p = Vector(x2, y2) + v;
    if (!judge(p)) {
        return false;
    }
    v = rotate90(v);
    p = p + v;
    return judge(p);
}

int main() {
#ifdef ExRoc
    freopen("test.txt", "r", stdin);
#endif // ExRoc
    ios::sync_with_stdio(false);

    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < n; ++j) {
            if (G[i][j] != '1') {
                continue;
            }
            for (int k = 0; k < n; ++k) {
                for (int l = 0; l < n; ++l) {
                    if (G[k][l] != '1') {
                        continue;
                    }
                    if (judge(i, j, k, l)) {
                        Vector v(k - i, l - j);
                        st.insert(v * v);
                    }
                }
            }
        }
    }
    st.erase(0);
    cout << st.size() << endl;

    return 0;
}