hdu1542 Atlantis
离散化的题目，和之前的大同小异
#include <iostream>
using namespace std;
const int size = 110;
double x[2*size], y[2*size];
double ax[size], bx[size], ay[size], by[size];
bool map1[2*size][2*size];
bool cmp(double a, double b)
{
return a < b;
}
int n;
int BinaryS(double ans, int st, int ed, double *x)//二分搜索查找每一个点的映射位置
{
int left = st, right = ed;
while (left <= right){
int mid = (left+right)/2;
if (x[mid] == ans){ return mid;}
if (x[mid] < ans){
left = mid+1;
}
if (x[mid] > ans){
right = mid-1;
}
}
}
int main()
{
int w, h;
int nc = 0;
int n;
while (scanf("%d", &n) && n){
int nx, ny;
nx = ny = 0;
int ii1 = 0;
for (int i = 0; i < n; i ++){
scanf("%lf%lf%lf%lf", &ax[ii1], &ay[ii1], &bx[ii1], &by[ii1]);
if (ax[ii1] > bx[ii1])swap(ax[ii1], bx[ii1]);
if (ay[ii1] > by[ii1])swap(ay[ii1], by[ii1]);
x[nx ++] = ax[ii1], y[ny ++] = ay[ii1];//将点依次分为x、y记录下来
x[nx ++] = bx[ii1], y[ny ++] = by[ii1];
ii1 ++;
}
int xx = 0, yy = 0;
for (int i = 1; i < nx; i ++){//去除相邻的x相等的情况
if (x[i] != x[i-1]){
xx ++;
x[xx] = x[i];
}
}
for (int i = 1; i < ny; i ++){//去除相邻的y相等的情况
if (y[i] != y[i-1]){
yy ++;
y[yy] = y[i];
}
}
sort(x, x+xx+1, cmp);//对x、y从小到大排序
sort(y, y+yy+1, cmp);
memset(map1, false, sizeof(map1));
for (int i = 0; i < ii1; i ++){
int sx = BinaryS(ax[i], 0, xx, x);//二分搜索查找每次输入的点的位置
int sy = BinaryS(ay[i], 0, yy, y);
int ex = BinaryS(bx[i], 0, xx, x);
int ey = BinaryS(by[i], 0, yy, y);
for (int ii = sx; ii < ex; ii ++){//进行映射
for (int j = sy; j < ey; j ++){
map1[ii][j] = true;
}
}
}
double sum = 0;
for (int i = 0; i < xx; i ++){
for (int j = 0; j < yy; j ++){
if (map1[i][j]){ //计算
sum += (x[i+1]-x[i])*(y[j+1]-y[j]);
}
}
}
printf("Test case #%d\n", ++nc);
printf("Total explored area: %.2lf\n\n", sum);
}
return 0;
}