contrast.c

cygwin下的包含各种c基本操作的demo程序

//----------------------------------------------
//            对称数
//----------------------------------------------


#include "my_common.h"
#ifdef __cplusplus
extern "C"
#endif

//#define _CONTRAST_DEBUG

int contrast(int data)
{
     char aa[32];
     char bb[32];
     int const_len=0;
     int ii=0;
     int len=0;
     int half_len=0;
     
     if (data < 0)
     {  return -1;}
     
     if(data < 10)
     {  return  0;}
     
     while(data/10)
     {
     	    aa[ii] = (data%10) + 48;
     	    data = data/10;
     	    #ifdef _CONTRAST_DEBUG
     	    printf("the aa[ii] is %c ,ii is %d\n",aa[ii],ii);
     	    #endif
     	    ii++;
     	}
     	aa[ii] = data + 48;
     	aa[ii+1] = 0;
     	
     	
     	
     	ii = 0;
     	
     	len = strlen(aa);
     	const_len = len;
	    #ifdef _CONTRAST_DEBUG
     	printf("the len is %d \n",len);
     	#endif
     	  	
     	half_len = len/2;
     	while ( len )
     	{
     	     	bb[len-1] = aa[ii];
            
            #ifdef _CONTRAST_DEBUG
     	      printf("the bb[len-1] is %c aa[ii] is %c,len-1 is %d,ii is %d\n",bb[len-1],aa[ii],len-1,ii);
     	      #endif 
            len--,ii++;    		
     	}
     	bb[const_len]='\0';
     	len = const_len;
     	ii = 0;
      #ifdef _CONTRAST_DEBUG	
     	printf("the data is %s \n",bb);
     	#endif 
     		
     	#ifdef _CONTRAST_DEBUG
     	printf("the half_len is %d \n",half_len);
     	#endif
     	
     	while (half_len--)       //note:在while中，half_len 是在执行循环体前减1
     	//for(;ii<half_len;ii++) // 在for中，ii是在循环体之后加一
     	{
     	     	if(bb[ii] == bb[len - ii - 1])
     	     	{ 
     	     		#ifdef _CONTRAST_DEBUG
     	     		printf("the char is %c ,half_len is %d \n",bb[ii],half_len);
     	     		#endif
     	     		ii++;
     	     	  continue;
     	     	}
     	     	else
     	     	{  /*half_len = -1;*/ break; }
     	     	
     	}
     	#ifdef _CONTRAST_DEBUG
     	printf("the half_len is %d \n",half_len);
     	#endif
     	//if (half_len != (ii ) )
     	if( half_len != -1)
     	{  
     		printf("%s is not a contrast data \n",bb);
     		return -1; 
     	}
     	
     	printf("the contrast data is %s \n",bb);
     	
     	return 0;
}