*结构-06. 复数四则运算

  1 /*
  2  * Main.c
  3  * F6-结构-06. 复数四则运算
  4  *  Created on: 2014年8月26日
  5  *      Author: Boomkeeper
  6  ********部分通过***********
  7  */
  8
  9 #include <stdio.h>
 10 #include <math.h>
 11
 12 #define EPSINON 0.1
 13
 14 /*
 15  * 复数结构体,c1、c2对应于题目中的c1、c2
 16  */
 17 struct complexNumber {
 18     float real;
 19     float imaginary;
 20 } c1, c2;
 21
 22 /*
 23  * 按照“(a1+b1i) 运算符 (a2+b2i) = 结果”的格式顺序输出2个复数
 24  * ch对应于"+" "-" "*" "/"4个运算符
 25  */
 26 void printComplex(struct complexNumber c1, char ch, struct complexNumber c2) {
 27
 28     if (c1.imaginary < 0) {
 29         if (c2.imaginary < 0)
 30             printf("(%.1f%.1fi) %c (%.1f%.1fi) = ", c1.real, c1.imaginary, ch,
 31                     c2.real, c2.imaginary);
 32         if (c2.imaginary > 0)
 33             printf("(%.1f%.1fi) %c (%.1f+%.1fi) = ", c1.real, c1.imaginary, ch,
 34                     c2.real, c2.imaginary);
 35     } else if (c1.imaginary > 0) {
 36         if (c2.imaginary < 0)
 37             printf("(%.1f+%.1fi) %c (%.1f%.1fi) = ", c1.real, c1.imaginary, ch,
 38                     c2.real, c2.imaginary);
 39         if (c2.imaginary > 0)
 40             printf("(%.1f+%.1fi) %c (%.1f+%.1fi) = ", c1.real, c1.imaginary, ch,
 41                     c2.real, c2.imaginary);
 42     }
 43 }
 44
 45 /*
 46  * 输出2个复数的和、差、积、商
 47  */
 48 void printResult(float re, float im) {
 49
 50     if (fabs(re) < EPSINON)
 51         re = 0;
 52     if (fabs(im) < EPSINON)
 53         im = 0;
 54
 55     if (re == 0 && im == 0)
 56         printf("0.0\n");
 57     else {
 58         if (re != 0 && im > 0)
 59             printf("%.1f+%.1fi\n", re, im);
 60         if (re != 0 && im < 0)
 61             printf("%.1f%.1fi\n", re, im);
 62         if (re != 0 && im == 0)
 63             printf("%.1f\n", re);
 64         if (re == 0 && im != 0)
 65             printf("%.1fi\n", im);
 66     }
 67 }
 68
 69 int main(void) {
 70
 71     float re = 0, im = 0; //临时变量,计算实部和虚部
 72
 73     scanf("%f %f %f %f", &c1.real, &c1.imaginary, &c2.real, &c2.imaginary);
 74
 75     //和
 76     printComplex(c1, ‘+‘, c2);
 77     re = c1.real + c2.real;
 78     im = c1.imaginary + c2.imaginary;
 79     printResult(re, im);
 80
 81     //差
 82     printComplex(c1, ‘-‘, c2);
 83     re = c1.real - c2.real;
 84     im = c1.imaginary - c2.imaginary;
 85     printResult(re, im);
 86
 87     //积
 88     printComplex(c1, ‘*‘, c2);
 89     re = c1.real * c2.real - c1.imaginary * c2.imaginary;
 90     im = c1.real * c2.imaginary + c1.imaginary * c2.real;
 91     printResult(re, im);
 92
 93     //商
 94     printComplex(c1, ‘/‘, c2);
 95     re = (c1.real * c2.real + c1.imaginary * c2.imaginary)
 96             / (c2.real * c2.real + c2.imaginary * c2.imaginary);
 97     im = (c1.imaginary * c2.real - c1.real * c2.imaginary)
 98             / (c2.real * c2.real + c2.imaginary * c2.imaginary);
 99     printResult(re, im);
100
101     return 0;
102 }

1.这个题目最让我抓心的是复数的虚部的符号的输出，复数四则运算还好计算，就是这个正负号，一不小心就乱了；

2.浮点数与0的比较，针对这道题目，因为输出结果只需要精确到0.1，所以<=0.1 && >=-0.1就判断为0。起初我参考了其他文章，按照0.00001来判断，输出结果总是不合题意。

题目链接：

http://pat.zju.edu.cn/contests/basic-programming/%E7%BB%93%E6%9E%84-06

参考：

http://blog.csdn.net/rabbit8848/article/details/30284651

http://blog.sina.com.cn/s/blog_64a475370101119h.html