得分:20

#include

#include

char symbol[] = {'+', '-', '*', '/', '='};

enum {

Add = 0,

Dec,

Mul,

Div,

Equ,

Max

};

int Judge(char c)

{

switch (c)

{

case '+':

return Add;

case '-':

return Dec;

case '*':

return Mul;

case '/':

return Div;

case '=':

return Equ;

default:

return -1;

}

}

double Calculate(double a, double b, int flag)

{

switch (flag)

{

case Add:

return a+b;

case Dec:

return a-b;

case Mul:

return a*b;

case Div:

return a/b;

default:

printf("Error!\n");

exit(1);

}

}

int main(void)

{

double a, b, answer;

char c;

int flag;

printf("Input format: a b \n");

while (1)

{

printf(">>> ");

scanf("%lf", &a);

while ((flag = Judge(c = getchar())) == -1);

scanf("%lf", &b);

while ((c = getchar()) != '\n');

answer = Calculate(a, b, flag);

printf(">>> %lf\n", answer);

}

}

随手写了个，功能不是很强，没有加纠错