在我的postfix评估代码我的解决功能不起作用请帮忙

问题描述

这是我的头文件：

this is my header file:

#include<stdio.h>
#include<ctype.h>
#define SIZE 50
#define MAX 30
char stack[SIZE] , infx[MAX] , pofx[MAX];
int top,stack1[SIZE];
void pushin(char);
char popout();
int prior(char);
int solve();
int push(int,int);
int pop(int);

THIS IS MY MAIN FILE:

#include"header.h"

int main()
{                         /* Main Program */
	char ch, elem;
	int i=0, k=0 ,val=0;
	top = -1;

	scanf("%s",infx);
	
	while( ( ch=infx[i++] ) != '\0' )
	{
		if( ch == '(')
		{ 
			pushin(ch);
		}
		else if( isalnum(ch) )
		{
			pofx[k++]=ch;
		}
		else if( ch == ')')
		{
			while( stack[top] != '(' )
                         {
		        	pofx[k++]=popout();
                         }
			      elem = popout(); /* Remove ( */
		}
		else
		{       /* Operator */
			while( prior( stack[top] ) >= prior(ch) )
				pofx[k++] = popout();
			pushin(ch);
		}
                  printf(" top.................>%d\n", top);
	}
	while( top != - 1 )
	{
		/* Pop from stack till empty */
		pofx[k++] = popout();
	}
	pofx[k] ='\0';          
	printf("%s(): Postfix:  %s\n" , __FUNCTION__, pofx);
        
        
           val = solve();
        
        printf("\n %d\n", val);

  return 0;     
}

THIS IS MY PUSHIN FUNCTION:

#include"header.h"
//push(char);
void pushin(char elem)
{                       /* Function for PUSH operation */
    stack[++top]=elem;
}

THIS IS MY POPOUT FUNCTION:

#include"header.h"

char popout( )
{
	if( top  == - 1 )
	{
		printf( "stack is empty\n" );
		return;
	}
	
	return( stack[top--]);

}

THIS IS MY PRIORITY FUNCTION:

#include"header.h"
int prior(char elem)
{                 /* Function for precedence */
    switch(elem)
    {
    case '#': return 0;
    case '(': return 1;
    case '+':
    case '-': return 2;
    case '*':
    case '/': return 3;
    }
}

THIS IS MY PUSH FUNCTION:

#include"header.h"

int push(int ele, int dup_top)
{
	printf("%d\t\t\t\t\t\t",dup_top);
   if(dup_top > SIZE)
	exit( 1 );
   dup_top = dup_top + 1;
   stack1[dup_top]= ele;
   printf("element ::%d", ele);
   printf("stack1[dup_top]===========%d\n",stack1[dup_top]);
   return dup_top ;
    

}


THIS IS MY POP FUNCTION:

#include"header.h"
int pop(int level_top)
{
	if(level_top == -1 )
	{
		printf( "stack is empty\n" );   
		return;
	}

        return(  stack1[level_top--] );

}


THIS IS MY SOLVE FUNCTION:

#include"header.h"

int solve()
{  
	int op1, op2 ,temp , i , j = 0 , result, ret_push, top1;
        int element;
	char ch;
        top1= -1;

	printf( "%s(): Entry\n", __FUNCTION__ );

	//while(ch = pofx[j++] != '\0')
        for(i=0;i<strlen(pofx);i++)>
	printf("%d.....",pofx[i]-'0');
	ch = pofx[j];
	while(ch != '\0')
	{
		top1 =-1;
			printf("%d\n\n\n\n",ch-'0');
	//	printf( "%s(): %c\n", __FUNCTION__, ch );
		if( isdigit(ch) )
		{
			printf("%d\n\n\n\n",ch-'0');
			printf( "Pushing %d to stack\n", ch - 48 );
          //              element = ch - '0';
		ret_push = push( (ch - 48) ,top1); /* Push the operand */
                        
                         
                         
			for( i=0; stack1[i]; i++ )
                         {
				printf( "push stack : %d\t" , stack1[i] );
                         }

				printf( "\n" );
		

                        printf( "no of elements in stack : %d\n" , top1 + 1 );
		}
		else
		{        /* Operator,pop two  operands */
		        op2= pop(ret_push);
			
                      for( i=0; stack1[i]; i++ )
                      {

		        printf( "pop stack : %d\t" , stack1[i]);
                      }
                                 
				printf( "\n" );
                       // printf("topstack= %d", topstack);
                       // pop();
		printf( "no of elements in stack : %d\n" , top1 +1 ); 

                        printf("op2 =  %d\n", op2);
	
			op1  = pop(ret_push);
			
                        for( i=0; stack1[i]; i++ )
                        {

				printf( "pop stack : %d\t" , stack1[i] );
                         }
                            
				printf( "\n" );
                       // printf("topstack: %d\n", topstack);
		printf( "no of elements in stack : %d\n" , top1 + 1 );

                        printf( "op1: %d\n", op1 );

			switch( ch )
			{
				case '+':temp = op1+op2 ;
					 break;
				case '-':temp = op1-op2 ;
					 break;
				case '*':temp = op1*op2 ;
					 break;
				case '/':temp = op1/op2 ;
					 break;
			}
			push( temp, top1 );
		}

		ch = pofx[++j];
	}

	result = pop(ret_push);


	printf( "%s(): result: %d\n", __FUNCTION__, result );

	return ( result );
}

[edit]已添加代码块 - OriginalGriff [/ edit]

[edit]Code block added - OriginalGriff[/edit]

推荐答案

int push(int ele, int dup_top)

您返回新的堆栈顶部索引。但是在你的求解函数中，你只需将该值赋给push_ret，并且永远不会更新你的top1变量。这是一个明显的错误。我建议更新push函数中的stack-top，如下所示：

You return the new stack top index. But in your solve function, you just assign that value to push_ret and never update your top1 variable. That is a clear mistake. I would recommend to update the stack-top inside your push function, like this:

void push (int value)
{
    stack1[++topIdx] = value;
}
// make topIdx a global variable and declare it next to stack1.

这同样适用于你的pop函数，它目前根本不会递减到顶部索引。它应该是：

The same applies to your pop function, which at the moment does not decrement to top index at all. It should read:

char pop ()
{
   return stack1[topidx--];
}

这将使您的代码更具可读性和正确性，至少是最严重的错误。

That would make your code much more readable and correct at least the most profound errors.

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