Ultraviolet A Problem 10209 is this integration? (Do you need points ?)

// Is this integration? (Do you need points ?) // PC/ultraviolet A IDs: 111307/10209, popularity: A, success rate: high level: 3 // verdict: accepted // submission date: 2011-11-01 // UV Run Time: 0.120 S // copyright (c) 2011, Qiu. Metaphysis # Yeah dot net // [solution] // set the area of the diagonal line to X, the area of the hitting part to Y, and the area of the grid part to Z, there are the following equations: /// x + 3 * Y/4 + z/2 = pI * a * A/4 // X + Y + z = A * A // the equation to be solved, there must be another unique Cube This can be obtained by calculating the area of the overlapping parts of the two 1/4 circles in the lower left and lower right corner. // This overlapping area is easy to calculate and can be obtained after careful observation. /// X + Y/2 + z/4 = pI * a * A/3-SQRT (3) * A/4 // three equations can be obtained: // X = A * a * (1-SQRT (3) + PI/3) // y = a * (2 * SQRT (3)-4 + PI/3) // z = A * a * (4-SQRT (3) -2 * PI/3) # include <iostream> # include <iomanip> # include <cmath> using namespace STD; # define PI 3.141592653589793int main (int ac, char * AV []) {double A, x, y, z; while (CIN> A) {x = A * a * (1-SQRT (3) + PI/3); y = a * (2 * SQRT (3)-4 + PI/3); Z = A * a * (4-SQRT (3) -2 * PI/3); cout. precision (3); cout. SETF (IOs: Fixed | IOs: showpoint); cout <x <"" <Y <"" <z <Endl;} return 0 ;}