usaa24/a1/program.c

162 lines
3.2 KiB
C

#include <stdio.h>
#include <assert.h>
#include <stdlib.h>
#include <ctype.h>
//// @
#define STACK_SIZE 200
struct Stack
{
char values[STACK_SIZE];
int size;
};
void push_stack(struct Stack* stack, float value);
char pop_stack(struct Stack* stack);
int count_stack(struct Stack* stack);
void push_stack(struct Stack* stack, char value)
{
assert(stack->size < STACK_SIZE);
stack->values[stack->size] = value;
stack->size += 1;
}
char pop_stack(struct Stack* stack)
{
assert(stack->size > 0);
char value = stack->values[stack->size-1];
stack->size -= 1;
return value;
}
int count_stack(struct Stack* stack)
{
return stack->size;
}
void print_stack(struct Stack* stack)
{
for (int i=0; i<stack->size; i++)
{
printf("%.2f ", stack->values[i]);
}
printf("\n");
}
char para(char c)
{
if(c=='(') return ')';
if(c=='<') return '>';
if(c=='{') return '}';
if(c=='[') return ']';
if(c==')') return '(';
if(c=='>') return '<';
if(c=='}') return '{';
if(c==']') return '[';
}
int main()
{
struct Stack mystack;
mystack.size=0;
char str[128];
scanf("%s", str);
printf("Read: %s", str);
int i=0;
char c, cs;
while(str[i]!='\0')
{
c=str[i];
if(c=='<'||c=='('||c=='{'||c=='[')
{
push_stack(&mystack, c);
}
if(c=='>')
{
cs=pop_stack(&mystack);
if(cs!='<')
{
printf("Crossed bracket %c in %d, expected %c", c, i);
}
}
}
int err=0;
char buf[505];
do
{
char* p=fgets(buf, 299, stdin);
if(p)
{
char c=buf[0];
float op1, op2, rez;
if(c=='+'||c=='-'||c=='/'||c=='*')
{
if(count_stack(&mystack)<2)
{
printf("not enough operands\n");
err=3;
break;
}
op2=pop_stack(&mystack);
op1=pop_stack(&mystack);
switch(c)
{
case '+': rez=op1+op2; break;
case '-': rez=op1-op2; break;
case '/':
if(c=='/' && op2==0)
{
err=1;
printf("division by zero\n");
}
else
rez=op1/op2;
break;
case '*': rez=op1*op2; break;
}
}
else
{
if(isdigit(c))
{
rez=atof(buf);
}
else
{
err=1;
printf("bad input\n");
}
}
if(!err)
{
if(count_stack(&mystack)==STACK_SIZE)
{
printf("full stack\n");
err=4;
break;
}
push_stack(&mystack, rez);
print_stack(&mystack);
}
}
else break;
}while(1);
if(!err)
printf("no input\n");
return 0;
}