usaa24/a1/program.c

#include <stdio.h>
#include <assert.h>
#include <stdlib.h>
#include <stdbool.h>

#define STACK_SIZE 200

struct Stack
{
   char values[STACK_SIZE];
   int size;
};

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("%c ", 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);
    fgets(str,100,stdin);
    if(str[strlen(str)-1]=='\n') { str[strlen(str)-1]='\0';}
    printf("Read: %s", str);

    int i=0;
    char c, cs;
    bool is_ok=true;
    while(str[i]!='\0' && is_ok)
    {
        c=str[i];
        if(c=='<'||c=='('||c=='{'||c=='[')
        {
           push_stack(&mystack, c); 
         
        }
        if(c=='>'||c==']'||c=='}'||c==')')
        {
            if(count_stack(&mystack)>0)
              cs=pop_stack(&mystack);
            else
            {
              printf("\nUnexpected closing bracket %c in %d\n", c,i);  
              is_ok=false;
              break;
            }
            if(c=='>' && cs!='<')
            {
                printf("\nCrossed bracket %c in %d, expected %c \n", c, i, para(cs));
                is_ok=false;
                break;
            }
            if(c==']' && cs!='[')
            {
                printf("\nCrossed bracket %c in %d, expected %c \n", c, i, para(cs));
                is_ok=false;
                break;
            }
            if(c==')' && cs!='(')
            {
                printf("\nCrossed bracket %c in %d, expected %c \n", c, i, para(cs));
                is_ok=false;
                break;
            }
            if(c=='}' && cs!='{')
            {
                printf("\nCrossed bracket %c in %d, expected %c \n", c, i, para(cs));
                is_ok=false;
                break;
            }
        }
        i++;
    }

    if(is_ok)
    {
       if(count_stack(&mystack)>0)
       {
         printf("\nMissing closing brackets: ");
         do
         {
            cs=pop_stack(&mystack);
            printf("%c", para(cs));    
         }while(count_stack(&mystack)>0);
         printf("\n");
      }
      else 
      printf("\nAll brackets OK\n");
    }


      
	return 0;
}