06a-guard-gallivant.cpp

#include <bits/stdc++.h>

using namespace std;
using ll = long long;

#ifdef _DEBUG
#include "utils/debug.h"
#else
#define debug(...) 0
#endif

int main() {
	cin.tie(0)->sync_with_stdio(0);
	string line;
	ll ans = 0;
	vector<string> g;
	while (getline(cin, line)) {
		g.push_back(line);
	}
	int N = g.size(), M = g[0].size();
	auto in = [&](int i, int j) { return i >= 0 && j >= 0 && i < N && j < M; };
	int x, y;
	for (int i = 0; i < N; ++i) {
		for (int j = 0; j < M; ++j) {
			if (g[i][j] == '^') x = i, y = j;
		}
	}
	int dx = -1, dy = 0;
	vector<vector<int>> vis(N, vector<int>(M));
	while (true) {
		vis[x][y] = 1;
		int nx = x + dx, ny = y + dy;
		if (!in(nx, ny)) break;
		if (g[nx][ny] == '#') {
			swap(dx, dy); dy *= -1;
		}
		else {
			x = nx, y = ny;
		}
	}
	for (int i = 0; i < N; ++i) for (int j = 0; j < M; ++j) {
		ans += vis[i][j];
	}
	cout << ans << '\n';
}