The full version of the calculator

#include<stdio.h>
#include<math.h>
#define PI 3.1415926535898
int jiemian(){
	int chose;
	printf("************************************\n");
	printf("============超级计算器==============\n");
	printf("************************************\n");
	printf("******                       *******\n");
	printf("*1.+ *                       *5.sin*\n");
	printf("******                       *******\n");
	printf("*2.- *       欢迎使用        *6.cos*\n");
	printf("******    作者：sweet girl     *******\n");
	printf("******                       *******\n");
	printf("*3.×*                       *7.tan*\n");
	printf("******                       *******\n");
	printf("*4.÷*                       *8.cot*\n");
	printf("******                       *******\n");
	printf("******-----------------------*******\n");
    printf("请输入您的选择：");
	scanf("%d",&chose);
	return chose;
}
void jiafa(){
    float jiashu,beijiashu;
	printf("请输入加数：\n");
    scanf("%f",&jiashu);
	printf("请输入被加数：\n");
	scanf("%f",&beijiashu);
	float res=jiashu+beijiashu;
	printf("%f+""%f=""%f\n",jiashu,beijiashu,res);
}
void jianfa(){
    float jianshu,beijianshu;
	printf("请输入减数：\n");
    scanf("%f",&jianshu);
	printf("请输入被减数：\n");
	scanf("%f",&beijianshu);
	float res=jianshu-beijianshu;
	printf("%f-""%f=""%f\n",jianshu,beijianshu,res);
}
void chengfa(){
    float chengshu,beichengshu;
	printf("请输入乘数：\n");
    scanf("%f",&chengshu);
	printf("请输入被乘数：\n");
	scanf("%f",&beichengshu);
	float res=chengshu*beichengshu;
	printf("%f*""%f=""%f\n",chengshu,beichengshu,res);
}
void chufa(){
    float chushu,beichushu;
	printf("请输入被除数：\n");
	scanf("%f",&beichushu);
	printf("请输入除数：\n");
    scanf("%f",&chushu);
    if(chushu==0){
	printf("除数不能为零，请重新输入：");
	chufa();}
	else{
	float res=beichushu/chushu;
	printf("%f÷""%f=""%f\n",beichushu,chushu,res);
}}
void zhengxuan(){
	float jiaodu;
	double res;
	printf("请输入正弦值：");
	scanf("%f",&jiaodu);
	res=sin(jiaodu*PI/180);
	printf("sin%f=%lf\n",jiaodu,res);
}
void yuxuan(){
	float jiaodu;
	double res;
	printf("请输入余弦值：");
	scanf("%f",&jiaodu);
	res=cos(jiaodu*PI/180);
	printf("cos%f=%lf\n",jiaodu,res);
}
void zhengqie(){
	float jiaodu;
	double res;
	printf("请输入正切值：");
	scanf("%f",&jiaodu);
	if(jiaodu==90){
	printf("难道你不知道正切没有90度吗？");
    zhengqie();	}
	else{
	res=tan(jiaodu*PI/180);
	printf("tan%f=%lf\n",jiaodu,res);
}}
void yuqie(){
	float jiaodu;
	double res;
	printf("请输入余切值：");
	scanf("%f",&jiaodu);
	if(jiaodu==180){
	printf("难道你不知道余切没有180度吗？");
    yuqie();	}
	else{
	res=1/tan(jiaodu*PI/180);
	printf("cot%f=%lf\n",jiaodu,res);
}}
void main(){
	switch(jiemian())
	{
	case 1:jiafa();main();break;
	case 2:jianfa();main();break;
	case 3:chengfa();main();break;
	case 4:chufa();main();break;
	case 5:zhengxuan();main();break;
	case 6:yuxuan();main();break;
	case 7:zhengqie();main();break;
	case 8:yuqie();main();break;
	default:printf("错了");main();break;
	}
}