Find the total area covered by two rectilinear rectangles in a 2D plane.
Each rectangle is defined by its bottom left corner and top right corner as shown in the figure.
Assume that the total area is never beyond the maximum possible value of int.
void swapTwo(int *A, int *B) { int tmp = *A; *A = *B; *B = tmp; } void sortFour(int *A, int *C, int *E, int *G) { int tmp = 0; if(*A > *C) swapTwo(A, C); if(*E > *G) swapTwo(E, G); if(*A > *E) swapTwo(A, E); if(*C > *E) swapTwo(C, E); if(*E > *G) swapTwo(E, G); } int computeArea(int A, int B, int C, int D, int E, int F, int G, int H) { int total = (C - A) * (D - B) + (G - E) * (H - F); if(A >= G || C <= E || B >= H || D <= F) return total; else { sortFour(&A, &C, &E, &G); sortFour(&B, &D, &F, &H); return total - (E - C) * (F - D); } }
int max(int a, int b) { if(a > b) return a; else return b; } int min(int a, int b) { if(a > b) return b; else return a; } int computeArea(int A, int B, int C, int D, int E, int F, int G, int H) { int total = (C - A) * (D - B) + (G - E) * (H - F); if(A >= G || C <= E || B >= H || D <= F) return total; int top = min(D, H); int bottom = max(B, F); int left = max(A, E); int right = min(C, G); return total - (top - bottom) * (right - left); }
原文：http://www.cnblogs.com/dylqt/p/4908217.html