#include <stdio.h>

short isNotEqual(char tmpChar, char* usedChars) {
	for (int i = 0; i < strlen(usedChars); i++)
		if (usedChars[i] == tmpChar)
			return 0;
	return 1;
}

void findEqualElem(char* str, char* newStr) {
	char tmpChar;
	int counter = 0;
	int index = 0;
	char usedChars[50];
	for (int i = 0; i < strlen(str); i++) {
		tmpChar = str[i];
		for (int j = i + 1; j < strlen(str); j++)
			if (tmpChar == str[j] && (isNotEqual(tmpChar, usedChars) == 1)) {
				counter++;
				newStr[index] = tmpChar;
				index++;
			}
		if (counter > 0) {
			newStr[index] = tmpChar;
			index++;
		}
		counter = 0;
		usedChars[i] = tmpChar;
	}
}

int main() {
	printf("Enter the string: ");
	char str[80];
	gets(str);
	char newStr[80];
	findEqualElem(str, newStr);
	printf("Result - ");
	int i = 0;
	while (newStr[i] > 0) {
		printf("%c", newStr[i]);
		i++;
	}
}