四则运算

一.作业要求

博客班级	https://edu.cnblogs.com/campus/ahgc/AHPU-se-JSJ18
作业要求	https://edu.cnblogs.com/campus/ahgc/AHPU-se-JSJ18/homework/11377
作业目标	学会使用markdown算法
学号	3180701339

二.题目要求

写一个能自动生成小学四则运算题目的程序，然后在此基础上扩展：
1）除了整数以外，还要支持真分数的四则运算，例如：1/6+1/8=7/24
2）程序要求能处理用户的输入，判断对错，累积分数
3）程序支持可以由用户自行选择加、减、乘、除运算
4）使用-n参数控制生成题目的个数，例如Myapp.exe -n 10，将生成10个题目

三.代码提交

include <stdio.h>
struct fraction {
int numerator;
int denominator;
};
// 求解最大公约数
int find_gcd(int n1, int n2);
// 将分数化为最简形式
struct fraction reduce_fraction(struct fraction f);
// 分数的四则运算
struct fraction add_fractions(struct fraction f1, struct fraction f2);
struct fraction subtract_fractions(struct fraction f1, struct fraction f2);
struct fraction multiply_fractions(struct fraction f1, struct fraction f2);
struct fraction divide_fractions(struct fraction f1, struct fraction f2);
int main(void)
{
struct fraction f = { 28, 4};
struct fraction f1 = { 7, 49 };
struct fraction f2 = { 8, 368 };

struct fraction reducedf = reduce_fraction(f);
printf("%d/%d reduced to simplest terms: %d/%d\n", f.numerator,
    f.denominator, reducedf.numerator, reducedf.denominator);

struct fraction addedf = add_fractions(f1, f2);
printf("%d/%d + %d/%d = %d/%d\n", f1.numerator, f1.denominator,
    f2.numerator, f2.denominator, addedf.numerator, addedf.denominator);

struct fraction subtractedf = subtract_fractions(f1, f2);
printf("%d/%d - %d/%d = %d/%d\n", f1.numerator, f1.denominator,
    f2.numerator, f2.denominator, subtractedf.numerator,
    subtractedf.denominator);

struct fraction multipliedf = multiply_fractions(f1, f2);
printf("%d/%d * %d/%d = %d/%d\n", f1.numerator, f1.denominator,
    f2.numerator, f2.denominator, multipliedf.numerator,
    multipliedf.denominator);

struct fraction dividedf = divide_fractions(f1, f2);
printf("%d/%d / %d/%d = %d/%d\n", f1.numerator, f1.denominator,
    f2.numerator, f2.denominator, dividedf.numerator,
    dividedf.denominator);
return 0;
}
int find_gcd(int n1, int n2)
{
int temp;
while (n1 != 0) {
    temp = n2 % n1;
    n2 = n1;
    n1 = temp;
}

return n2;
}
struct fraction reduce_fraction(struct fraction f)
{
int gcd = find_gcd(f.numerator, f.denominator);
f.numerator /= gcd;
f.denominator /= gcd;
return f;
}
struct fraction add_fractions(struct fraction f1, struct fraction f2)
{
f1.numerator *= f2.denominator;
f2.numerator *= f1.denominator;
struct fraction result = {
    f1.numerator + f2.numerator,
    f1.denominator * f2.denominator
};
result = reduce_fraction(result);

return result;
}
struct fraction subtract_fractions(struct fraction f1, struct fraction f2)
{
f1.numerator *= f2.denominator;
f2.numerator *= f1.denominator;
struct fraction result = {
    f1.numerator - f2.numerator,
    f1.denominator * f2.denominator
};
result = reduce_fraction(result);

return result;
}
struct fraction multiply_fractions(struct fraction f1, struct fraction f2)
{
struct fraction result = {
f1.numerator * f2.numerator,
f1.denominator * f2.denominator
};
result = reduce_fraction(result);
return result;
}
struct fraction divide_fractions(struct fraction f1, struct fraction f2)
{
struct fraction result = {
f1.numerator * f2.denominator,
f1.denominator * f2.numerator
};
result = reduce_fraction(result);
return result;
}

小结

一开始博客园的使用并不顺利，给我造成了许多困难。在上网查询资料和同学的帮助下才顺利完成。markdown语法的运用让我们用处颇深。
psp表格

psp2.1	任务内容	计划所需时间min	实际完成时间min
Planning	计划	10	15
Estimate	估计这个任务需要多少时间，并规划大致工作步骤	5	5
Development	开发	100	120
Analysis	需求分析（包括学习新技术）	10	15
Design Spec	生成设计文档	20	22
Design Review	设计复审	10	10
Coding Standard	代码规范	5	10
Design	具体设计	15	20
Coding	具体编码	40	42
Code Review	代码复审	3	4
Test	测试	15	20
Reporting	报告	10	17
Test Report	测试报告	4	4
Size	计算工作量	3	3
Postmortem & Process Improvement Plan	事后总结，并提出过程改进计划	5	5