```
class Solution {
public:
bool increasingTriplet(vector<int>& nums) {
int first_pile = INT_MAX;
int second_pile = INT_MAX;
for (int num : nums) {
if (num <= first_pile) {
first_pile = num;
} else if (num <= second_pile) {
second_pile = num;
} else {
return true;
}
}
return false;
}
};
```

See Also: