[Topcoder] SRM211

 DivI lev2

 

定义grid，0为空，1代表有障碍或已考虑

从每个格式开始flood fill一遍，记录flood fill的格子数量

#include <iostream>#include <queue>#include <vector>#include <cstring>#include <sstream>#include <algorithm>#define HEIGHT400#define WIDTH600using namespace std;typedef struct pixel {int x;int y;} pixel;const int xoffset[4] = {1, 0, -1, 0};const int yoffset[4] = {0, 1, 0, -1};class grafixMask {private:vector<int>holes;int grid[HEIGHT][WIDTH];intisValid(pixel n) {if (n.x < 0 || n.x > HEIGHT - 1 || n.y < 0 || n.y > WIDTH - 1 || grid[n.x][n.y])return 0;return 1;}public:vector<int> sortedAreas(vector<string> rectangles) {memset(grid, 0, sizeof(int) * HEIGHT * WIDTH);for (int i = 0; i < rectangles.size(); i++) {istringstream ss(rectangles[i]);int tlx, tly, brx, bry;ss >> tlx >> tly >> brx >> bry;for (int x = tlx; x <= brx; x++)for (int y = tly; y <= bry; y++)grid[x][y] = 1;}for (int x = 0; x < HEIGHT; x++)for (int y = 0; y < WIDTH; y++) {if (grid[x][y] == 1)continue;//cout << "x = " << x << " y = " << y << endl;queue<pixel> q;int cnt = 1;pixel p;p.x = x; p.y = y;grid[x][y] = 1;q.push(p);while (!q.empty()) {p = q.front();q.pop();pixel newp;for (int i = 0; i < 4; i++) {newp.x = p.x + xoffset[i];newp.y = p.y + yoffset[i];if (isValid(newp)) {cnt++;//cerr << cnt << endl;grid[newp.x][newp.y] = 1;q.push(newp);}}}holes.push_back(cnt);}sort(holes.begin(), holes.end());return holes;}};int main(){grafixMask gm;// example 0cout << "example 0: " << endl;vector<string> vec;vec.push_back("0 292 399 307");vec.push_back("0 292 399 307");vector<int>res = gm.sortedAreas(vec);return 0;}