Merkkijono

#include "stdio.h"
#include "stdlib.h"

int parse( char *, int *);

int main ( int argc, char ** argv ){
	//Get String
	char * str = (char *)malloc(sizeof(char));
	int i = 0;
	str[0] = getchar();
	while (1) {
		if (str[i]== EOF){
			str[i] = '\0';
			break;
		}
		i++;
		str = (char *)realloc(str, (i+2)*sizeof(char));
		str[i] = getchar();

	}
	
	int * index = (int *)malloc((i + 1) * sizeof(int));
	int j = 0;
	while(str[j]){
		index[j] = 1;
		j++;
	}
	index[j] = '\0';

	//Parse String
	while(parse(str, index)) continue;
	
	//Print String
	j = 0;
	while(str[j]){
		if (index[j]){
			putchar(str[j]);
		}
		j++;
	}
	

	free(str);
	free(index);
	return 0;
}


int parse(char * str, int * index) {
	int i = 0;
	int j = 0;
	while (str[i]) {
		if (!index[i]) {
			i++;
			continue;
		}
		//First element of array
		if (i == 0){
			
			if (!index[i+1]) {
				// + SIDE 0
				int ii = 1;
				while (index[i+ii] == 0){
					if (str[i+ii] == '\0') break;
					if (str[i] == str[i + ii]){
						index[i] = 0;
						j++;
						break;
					}
					ii++;
				}
				if (str[i] == str[i+ii]){
					index[i] = 0;
					index[i+ii] = 0;
					j++;
				}
			}
			else {
				// + SIDE 1
				if (str[i] == str[i+1]){
				index[i] = 0;
				index[i+1] = 0;
				j++;
				}
			}
			i++;
			continue;
		}
		if (!index[i+1] && !index[i-1]) {
			//BOTH SIDES 0
			//Check + side
			int ii = 1;
			while (index[i+ii] == 0){
				if (str[i+ii] == '\0') break;
				if (str[i] == str[i + ii]){
					index[i] = 0;
					j++;
					break;
				}
				ii++;
			}
			if (str[i] == str[i+ii]){
				index[i] = 0;
				index[i+ii] = 0;
				j++;
			}
			//Check - side
			ii = 1;
			while (index[i-ii] == 0){
				if (ii == i){
					break;
				}
				if (str[i] == str[i - ii]){
					index[i] = 0;
					j++;
					break;
				}
				ii++;
			}
			if (str[i] == str[i-ii]){
				index[i] = 0;
				index[i-ii] = 0;
				j++;
			}

		}
		else if (!index[i+1]) {
			// + SIDE 0
			//Check - side
			if (str[i] == str[i-1]){
				index[i] = 0;
				index[i-1] = 0;
				j++;
			}
			//Check + side
			else{
				int ii = 1;
				while (index[i+ii] == 0){
					if (str[i+ii] == '\0') break;
					if (str[i] == str[i + ii]){
						index[i] = 0;
						j++;
						break;
					}
					ii++;
				}
				if (str[i] == str[i+ii]){
					index[i] = 0;
					index[i+ii] = 0;
					j++;
				}
			}
		}
		else if (!index[i-1]) {
			// - SIDE 0
			//check + side
			if (str[i] == str[i+1]){
				index[i] = 0;
				index[i+1] = 0;
				j++;
			}
			//Check - side
			else{
				int ii = 1;
				while (index[i-ii] == 0){
					if (ii == i){
						break;
					}
					if (str[i] == str[i - ii]){
						index[i] = 0;
						j++;
						break;
					}
					ii++;
				}
				if (str[i] == str[i-ii]){
					index[i] = 0;
					index[i-ii] = 0;
					j++;
				}
			}
		}
		else {
			//BOTH SIDES 1
			if (str[i] == str[i+1]) {
				index[i] = 0;
				index[i+1] = 0;
				j++;
			}
			if (str[i] == str[i-1]) {
				index[i] = 0;
				index[i-1] = 0;
				j++;
			}
		}
		i++;
	}
	if (j > 0) return 1;
	return 0;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: WRONG ANSWER

Test 5

Verdict: WRONG ANSWER

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED