（非完成版）C++实现科学计算器主函数代码，（不含调用函数）

C++作业，为方便复制所以写了CSDN，匹配度仅供作业小组人员使用

#include
using namespace std;

int key1() {
	int k1;
	cout << "请问是否需要对该数字进行预处理,如不需要请输入0：" << endl;
	cout << "1.sin   2.cos  3.tan " << endl;
	cin >> k1;
	while (k1 != 1 && k1 != 2 && k1 != 3 && k1 !=0 ) {
		cout << "请重新输入" << endl;
		cin >> k1;
	}
	switch (k1) {
	case 1:
		return 1;
	case 2:
		return 2;
	case 3:
		return 3;
	case 4:break;
	}
}

void key2( double *cal, int a) {
	double c = *cal;
	switch (a) {//所有涉及cal的都用c来表示
	case 1:
		//sinc
		break;
	case 2:
		//cosc
		break;
	case 3:
		//tanc
		break;
	}
	*cal = c;
}

int keys(double *cal) {
	int b1;
	double b2,c;
	c = *cal;
	cout << "请输入你所需要的运算符或运算方式前的编号，其中第8个是结束运算：" << endl;
	cout << "************************************" << endl;
	cout << "*   1. ＋   2. —   3. ×   4. ÷  *" << endl;
	cout << "*   5.n√   6. ^n   7.1/X   8. FIN *" << endl;
	cout << "************************************" << endl;
	cin >> b1;
	int a = key1();
	cout << "请输入下一个数,如果你已经结束运算请随意输入数字" << endl;
	cin >> b2;
	key2(&b2,a);
	while (b1 != 8) {
		switch (b1) {
		case 1:
			c += b2;
			break;
		case 2:
			c -= b2;
			break;
		case 3:
			c *= b2;
			break;
		case 4:
			c /= b2;
			break;
		case 5:
			//需编写
			break;
		case 6:
			//需编写
			break;
		case 7:
			//需编写
			break;
	    }
	    *cal = c;
		return 0;
    }
	if(b1==8){
		*cal = c;
		return 1;
	}
}

void tools(){
	int a;
	cout << "请选择您需要的工具" << endl;
	cout << "1. 水仙花数" << endl;
	cout << "2. 最大公因数" << endl;
	cout << "3. 最小公倍数" << endl;
	cout << "4. 素数" << endl;
	cout << "5. 阶乘" << endl;
	cin >> a;
	switch(a){
	case 1:
		//函数调用
		break;
	case 2:
		break;
	case 3:
		break;
	case 4:
		break;
	case 5:
		break;
	}
}

void calculation() {
	double cal=0;
	int a = key1();
	cout << "请输入数字：" << endl;
	cin >> cal;
	key2(&cal,a);
	int n = 0;
	while (n == 0) {
	     n = keys(&cal);
	}
	cout << cal<< endl;

}

int main() {
	int a1=0;
	cout << "欢迎使用科学计算器！请选择您需要的功能" << endl;
	cout << "1.工具" << endl;
	cout << "2.计算" << endl;
	cin >> a1;
	while (a1 != 1 && a1 != 2) {
        cout << "请重新输入" << endl;
		cin >> a1;
	}
	if (a1 == 1) {
		tools();
	}
	else if (a1 == 2) {
		calculation();
	}
}