Assembler Program in C

#include

#include

#include

void push(char [], int *, char [], int *);

char pop(char [], int *);

void push1(char, int *, char [], int *);

void main()

{

int i=0,top=-1,k=1,j,n;

char str[30],stack[20],lhs,rhs,ch;

clrscr();

printf("Enter the postfix expression: ");

scanf("%[^\n]s",str);

j = strlen(str);

str[j] = '#';

while(str[i] != '#')

{

if(isalpha(str[i]))

push(str,&i,stack,&top);

else

{

rhs = pop(stack,&top);

lhs = pop(stack,&top);

j = lhs;

n = rhs;

if(j >= 0 && j <= 9)

printf("LOD T%d\n",lhs);

else

printf("LOD %c\n",lhs);

if(n >= 0 && n <= 9)

{

switch(str[i])

{

case '+':

printf("ADD T%d\n",rhs);

break;

case '-':

printf("SUB T%d\n",rhs);

break;

case '*':

printf("MUL T%d\n",rhs);

break;

case '/':

printf("DIV T%d\n",rhs);

break;

}

}

else

{

switch(str[i])

{

case '+':

printf("ADD %c\n",rhs);

break;

case '-':

printf("SUB %c\n",rhs);

break;

case '*':

printf("MUL %c\n",rhs);

break;

case '/':

printf("DIV %c\n",rhs);

break;

}

}

ch = (char)k++;

printf("STO T%d\n",ch);

push1(ch,&i,stack,&top);

}

}

getch();

}

void push(char str[], int *i, char stack[], int *top)

{

(*top)++;

stack[*top] = str[(*i)++];

}

char pop(char stack[], int *top)

{

return stack[(*top)--];

}

void push1(char ch, int *i, char stack[], int *top)

{

(*top)++; (*i)++;

stack[*top] = ch;

}