Lang:GCC
Edit12345678910111213141516171819202122232425262728293031#include <stdio.h>#include <stdlib.h>#include <string.h>int diff(char* substr);int comp(const void * a, const void * b);int main(){int fibonacci[7] = {1, 2, 3, 5, 8, 13, 21};// loop counterint i, j;//length of main strint len;//main stringchar str[102];//substringchar* substr;//number of different lettersint diffNum;//string listchar* list[5100];//index of list;int index;gets(str);len = strlen(str);index = 0;for (i = 0; i <= len - 1; i++)