给你两个矩形，问你他们的重叠面积是多少。
思路：
这两个矩形是平行x和y轴的，所以水题，不解释。
#include<stdio.h> typedef struct { double x ,y; }NODE; NODE a ,b ,c ,d; int main () { double x1 ,x2 ,y1 ,y2; double x11 ,x22 ,y11 ,y22; while(~scanf("%lf %lf %lf %lf %lf %lf %lf %lf" ,&a.x ,&a.y ,&b.x ,&b.y ,&c.x ,&c.y ,&d.x ,&d.y)) { x1 = x11 = 1000000000.0 ,x2 = x22 = 0; y1 = y11 = 1000000000.0 ,y2 = y22 = 0; x1 = a.x < b.x ? a.x : b.x; x2 = a.x > b.x ? a.x : b.x; y1 = a.y < b.y ? a.y : b.y; y2 = a.y > b.y ? a.y : b.y; x11 = c.x < d.x ? c.x : d.x; x22 = c.x > d.x ? c.x : d.x; y11 = c.y < d.y ? c.y : d.y; y22 = c.y > d.y ? c.y : d.y; double x = x1 > x11 ? x1 : x11; double xx = x2 < x22 ? x2 : x22; double y = y1 > y11 ? y1 : y11; double yy = y2 < y22 ? y2 : y22; if(xx - x <= 0 || yy - y <= 0) puts("0.00"); else printf("%.2lf " ,(xx - x) * (yy - y)); } return 0; }