[003] largest_subarray_with_equal_1&0

[Description] Given an array with only '1' and '0', find a largest length sub-array which contains equal number of '1' and '0'. Return the largest number.

e.g. arr[] = {1,0,1,0,0,0,1,1,0,1,1,0,1,1,1,0,0,1,1,1,0,1,0,1,1}

　　return : 16

[Thought] Preprocess this array by add 1/-1 to arr[i] while arr[i] is 1/0; find the last position of '0' as 'largest1'; find the farther distance of the same number as 'largest2'; return the larger one of 'largest1' and 'largest2'.　　O(n^2)

[Implementation] C code:

 #include<stdio.h>

 int largestSubarray(int str[],int size)
 {
         int largest=;
         int i,j;
         str[]?(str[]=):(str[]=-);
         // preprocess.
         for(i=;i<size;i++)
         {
                 str[i]?(str[i]=str[i-]+):(str[i]=str[i-]-);
         }
         // find the last 0's position, and find the farther distance of the same numbers.
         for(i=;i<size;i++)
         {
                 // find the last 0's position.
                 if( == str[i] && (i+)>largest)
                 {
                         largest=i+;
 //                      printf("0:%d\n",largest);
                 }
                 // find the farther distance of the same numbers.
                 for(j=;j<i;j++)
                 {
                         if(str[i] == str[j] && (i-j)>largest)
                         {
                                 largest=i-j;
 //                              printf("other:%d\n",largest);
                                 break;
                         }
                 }
         }
         return largest;
 }

 int main()
 {
         int str[]={,,,,,,,,,,,,,,,,,,,,,,,,};
         int size=sizeof(str)/sizeof(str[]);
         int i;

         printf("Initianl Sequence which size is %d :\n",size);
         for(i=;i<size;i++)
         {
                 printf("%d, ",str[i]);
         }
         printf("\nlargest:%d\n",largestSubarray(str,size));
 }