这是一个简易计算器的代码，我在vs里运行的时候总会弹出错误弹窗，萌新实在看不出哪里的问题，求大佬解答。```c

#include<stdio.h>
int main()
{
	float a, b,c;
	char o,op;
	begin:
	scanf_s("%.2f%c%.2f", &a,&op,&b);
	if (op == '+')
	{
		c = a + b;
		printf("%.2f+%.2f=%.2f", a, b, c);
	}
	else if (op == '-')
	{
		c = a - b;
		printf("%.2f-%.2f=%.2f", a, b, c);
	}
	else if (op == '*')
	{
		c = a * b;
		printf("%.2f*%.2f=%.2f", a, b, c);
	}
	else if (op == '/')
	{
		c = a / b;
		printf("%.2f/%.2f=%.2f", a, b, c);
	}
	scanf_s("%c", &o);
	if (o == 'y')
	{
		goto begin;
	}
	else if (o == 'n')
	{
		return 0;
	}
	else if (o!='y'&&o!='n')
	{
		printf("error");
		goto begin;
	}

}