```
class Solution {
public:
bool increasingTriplet(vector<int>& nums) {
int N = nums.size();
if(N < 3){
return false;
}
int a = INT_MAX, b = INT_MAX;
for(int i = 0; i < N; i++){
if(b < nums[i] ){
return true;
}
else if(a < nums[i]){
b = nums[i];
}
else{
a = nums[i];
}
}
return false;;
}
};
```