9.18随笔

用c++实现一个程序：

任意生成30道两位数四则运算题目，要求：减法输出结果不可以出现负数，除法输出结果不能有小数，乘法输出结果位数不可超过999.

代码实现

#include <iostream>
#include <cstdlib>
#include <ctime>
using namespace std;

int generateNumber(int min, int max) {
return min + rand() % (max - min + 1);
}

char generateOperator() {
char operators[] = {'+', '-', '*', '/'};
int index = rand() % 4;
return operators[index];
}

bool checkSubtraction(int operand1, int operand2) {
return operand1 >= operand2;
}

bool checkMultiplication(int operand1, int operand2) {
return operand1 * operand2 <= 99;
}

bool checkDivision(int operand1, int operand2) {
return operand1 % operand2 == 0;
}

int main() {
srand(time(0));

int correctCount = 0;
int wrongCount = 0;

for (int i = 0; i < 30; i++) {
int operand1 = generateNumber(10, 99);
int operand2 = generateNumber(10, 99);
char op = generateOperator();

int result = 0;
string operatorStr;

switch (op) {
case '+':
result = operand1 + operand2;
operatorStr = "+";
break;
case '-':
if (!checkSubtraction(operand1, operand2)) {
i--;
continue;
}
result = operand1 - operand2;
operatorStr = "-";
break;
case '*':
if (!checkMultiplication(operand1, operand2)) {
i--;
continue;
}
result = operand1 * operand2;
operatorStr = "*";
break;
case '/':
if (!checkDivision(operand1, operand2)) {
i--;
continue;
}
result = operand1 / operand2;
operatorStr = "/";
break;
}

int answer;
cout << "题目" << i+1 << ": " << operand1 << " " << operatorStr << " " << operand2 << " = ";
cin >> answer;

if (answer == result) {
cout << "回答正确！" << endl;
correctCount++;
} else {
cout << "回答错误！" << endl;
wrongCount++;
}
}

cout << "回答正确的题目数量: " << correctCount << endl;
cout << "回答错误的题目数量: " << wrongCount << endl;

return 0;
}

//这个代码还需改进，求大佬指点迷津。