.ccls-cache
main
main.c
Makefile
Config files
.replit
replit.nix
#include<stdio.h>
#include<stdlib.h>
#include<math.h>
#define MAXOP 100
#define NUMBER '0'
int getop(char []);
void push(double);
double pop(void);
/* reverse polish calculator */
int main(void)
{
int type;
double op2,op1;
char s[MAXOP];
void clearsp(void);
while((type = getop(s)) != EOF)
{
switch(type)
{
case NUMBER:
push(atof(s));
break;
case '+':
push(pop()+pop());
break;
case '*':
push(pop()*pop());
break;
case '-':
op2 = pop();
push(pop()-op2);
break;
case '/':
op2 = pop();
if(op2 != 0.0)
push(pop()/op2);
else
printf("error:zero divisor\n");
break;
case '%':
op2 = pop();
if(op2 != 0.0)
push(fmod(pop(),op2));
else
printf("erro:zero divisor\n");
break;
case '?':
op2=pop();
printf("\t%.8g\n",op2);
push(op2);
break;
case 'c':
clearsp();
break;
case 'd':
op2=pop();
push(op2);
push(op2);
break;
case 's':
op1=pop();
op2=pop();
push(op1);
push(op2);
break;
case '\n':
printf("\t%.8g\n",pop());
break;
default:
printf("error: unknown command %s\n",s);
break;
}
}
return 0;
}
#define MAXVAL 100
int sp = 0;
double val[MAXVAL];
void push(double f)
{
if(sp < MAXVAL)
val[sp++]=f;
else
printf("error:stack full, cant push %g\n",f);
}
double pop(void)
{
if(sp>0)
return val[--sp];
else
{
printf("error: stack empty\n");
return 0.0;
}
}
void clearsp(void)
{
sp = 0;
}
#include<ctype.h>
int getch(void);
void ungetch(int);
int getop(char s[])
{
int i,c;
while((s[0] = c = getch()) == ' ' || c =='\t')
;
s[1] = '\0';
i = 0;
if(!isdigit(c) && c!='.' && c!='-')
return c;
if(c=='-')
if(isdigit(c=getch()) || c == '.')
s[++i]=c;
else
{
if(c!=EOF)
ungetch(c);
return '-';
}
if(isdigit(c))
while(isdigit(s[++i] =c =getch()))
;
if(c=='.')
while(isdigit(s[++i] = c=getch()))
;
s[i] = '\0';
if(c!=EOF)
ungetch(c);
return NUMBER;
}
#define BUFSIZE 100
char buf[BUFSIZE];
int bufp = 0;
int getch(void)
{
return (bufp > 0) ? buf[--bufp] : getchar();
}
void ungetch(int c)
{
if(bufp >= BUFSIZE)
printf("ungetch: too many characters\n");
else
buf[bufp++] = c;
}