#include<bits/stdc++.h>
// Υ»
struct Stack {
	int s[100];
	int top;
} stack;

int main(void) {
	char left_d = '{';
	char left_z = '[';
	char left_x = '(';
	char right_d = '}';
	char right_z = ']';
	char right_x = ')';
	int flag = 1;
	int have_other_word = 0;
	int i;

	// ΆΣΑΠ
	char que[100];
	int head = 0;
	int tail = 0;


	stack.top = 0;

	gets(que);

	tail = strlen(que);

	for (i = 0; i < tail; i++) {
		if (
		    que[i] != left_d &&
		    que[i] != left_z &&
		    que[i] != left_x &&
		    que[i] != right_d &&
		    que[i] != right_z &&
		    que[i] != right_x
		) {
			have_other_word = 1;
			break;
		}
	}

	if (have_other_word == 0) {
		while (head < tail) {
			if (que[head] == left_d || que[head] == left_z || que[head] == left_x) {
				stack.s[stack.top] = head;
				stack.top++;
			} else {
				if (que[head] == right_d) {
					if (que[stack.s[stack.top - 1]] == left_d) {
						stack.top--;
					} else {
						flag = 0;
					}
				}

				if (que[head] == right_z) {
					if (que[stack.s[stack.top - 1]] == left_z) {
						stack.top--;
					} else {
						flag = 0;
					}
				}

				if (que[head] == right_x) {
					if (que[stack.s[stack.top - 1]] == left_x) {
						stack.top--;
					} else {
						flag = 0;
					}
				}
			}

			if (flag == 0) {
				break;
			}

			head++;
		}
	} else {
		flag = 0;
	}

	if (flag) {
		printf("YES\n");
	} else {
		printf("NO\n");
	}

	return 0;
}