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#include <iostream>
#include <vector>
#include <algorithm>
#include <stack>
//#include <gtest/gtest.h>
using std::vector;
using std::ios_base;
using std::cin;
using std::cout;
using std::endl;
class TreeOrders {
public:
int n;
vector<long> key;
vector<int> left;
vector<int> right;
void read() {
cin >> n;
key.resize(n);
left.resize(n);
right.resize(n);
for (int i = 0; i < n; i++) {
cin >> key[i] >> left[i] >> right[i];
}
}
bool is_Bst() {
if (key.size()==0) return true;
std::stack<int> keyIndexStack;
vector<long> result;
bool walkLeft = true;
int currentIndex = 0;
keyIndexStack.push(currentIndex);
while (!keyIndexStack.empty() || right[currentIndex] != -1) {
if (walkLeft) {
if (left[currentIndex] != -1) {
if (key[left[currentIndex]] >= key[currentIndex]) return false;
currentIndex = left[currentIndex];
keyIndexStack.push(currentIndex);
} else {
int i = keyIndexStack.top();
keyIndexStack.pop();
if (result.size() > 0) {
if (key[i] < result[(result.size()-1)]) return false;
}
result.push_back(key[i]);
walkLeft = false;
}
} else {
if (right[currentIndex] != -1) {
if (key[right[currentIndex]] < key[currentIndex]) return false;
currentIndex = right[currentIndex];
keyIndexStack.push(currentIndex);
walkLeft = true;
} else {
if (!keyIndexStack.empty()) {
currentIndex = keyIndexStack.top();
keyIndexStack.pop();
if (result.size() > 0) {
if (key[currentIndex] <= result[(result.size()-1)]) return false;
}
result.push_back(key[currentIndex]);
}
}
}
}
return true;
}
};
void print(vector<int> a) {
for (size_t i = 0; i < a.size(); i++) {
if (i > 0) {
cout << ' ';
}
cout << a[i];
}
cout << '\n';
}
//TEST(TreeTraversal, t) {
// TreeOrders t;
// t.key = {4, 2, 5, 1, 3};
// t.left = {1, 3, -1, -1, -1};
// t.right = {2, 4, -1, -1, -1};
//
// vector<int> results = t.in_order();
// ASSERT_EQ(5, results.size());
// ASSERT_EQ(1, results[0]);
// ASSERT_EQ(2, results[1]);
// ASSERT_EQ(3, results[2]);
// ASSERT_EQ(4, results[3]);
// ASSERT_EQ(5, results[4]);
//
// results = t.pre_order();
// ASSERT_EQ(5, results.size());
// ASSERT_EQ(4, results[0]);
// ASSERT_EQ(2, results[1]);
// ASSERT_EQ(1, results[2]);
// ASSERT_EQ(3, results[3]);
// ASSERT_EQ(5, results[4]);
//
// results = t.post_order();
// ASSERT_EQ(5, results.size());
// ASSERT_EQ(1, results[0]);
// ASSERT_EQ(3, results[1]);
// ASSERT_EQ(2, results[2]);
// ASSERT_EQ(5, results[3]);
// ASSERT_EQ(4, results[4]);
//}
int main_with_large_stack_space() {
ios_base::sync_with_stdio(0);
TreeOrders t;
t.read();
if (t.is_Bst())
cout << "CORRECT" << endl;
else
cout << "INCORRECT" << endl;
return 0;
}
int main (int argc, char **argv)
{
return main_with_large_stack_space();
}
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