原题:

思路: 就是数学公式, 感觉这题不是考算法而是考语言的.

+.2f保留两位小数, 并且正数前面添加"+"号(第2个测试点)

C语言会把类似于-0.004四舍五入成-0.00, 如果没注意这点最后两个

测试点过不去.

实现:

#include 
    
     #include 
     
      int main (void) {    double R1;    double P1;    double A1;    double B1;    double A;    double R2;    double P2;    double A2;    double B2;    double B;    scanf("%lf %lf %lf %lf", &R1, &P1, &R2, &P2);    A1 = R1 * cos(P1);    B1 = R1 * sin(P1);    A2 = R2 * cos(P2);    B2 = R2 * sin(P2);    A = A1 * A2 - B1 * B2;    B = A1 * B2 + A2 * B1;    if(A > -0.005 && A < 0) A = 0; // (-0.005, 0)    if(B > -0.005 && B < 0) B = 0; // (-0.005, 0)    printf("%.2f%+.2fi", A, B);        return 0;}