C language · Delete duplicate elements

Algorithm increase 11-2 Delete repeating element time limit: 10.0s memory limit: 256.0MBThe problem is described as the library design new function Delpack, which deletes all the repeating elements in the input string. Discontinuous repeating elements are also removed.
A function is required, and a pointer operation is used inside the function. Sample input 1223445667889 Sample output 13579 sample input else sample output LS data size and convention string array maximum length is 100.

1 /*2 Ideas:3 The string is stored in the character array A, and the value is copied to array B, and each element of B is traversed4 The corresponding element in B is set to-1, compared to each element in a. 5 An element in output B that is not-1. 6 */ 7#include <stdio.h>8#include <string.h>9 Chara[ -],b[ -];Ten voidDel (intIndexintLen) { One      for(intI=0; i<len;i++){ A         if(index = = i)Continue;//Subscript is the same as the same element does not compare, into the next loop -         if(B[index] = = A[i]) b[index]=-1;//have the same element with a value of-1 -     } the } - intMain () { - gets (a); -memcpy (B,a,sizeof(a));//Copy the elements of A to B +     intLen=strlen (a);//find the length of a -      for(intI=0; i<len;i++){ + Del (I,len); A     } at      for(intI=0; i<len;i++) {//elements of non-1 in output B -         if(b[i]!=-1){ -printf"%c", B[i]); -         } -     } -     return 0; in}

C language · Delete duplicate elements