Easy
Can Make Arithmetic Progression From Sequence — C++
Full explanation · Time O(n) · Space O(1)
// Time: O(n)
// Space: O(1)
class Solution {
public:
bool canMakeArithmeticProgression(vector<int>& arr) {
const auto m = *min_element(cbegin(arr), cend(arr));
const auto& d = (*max_element(cbegin(arr), cend(arr)) - m) / (arr.size() - 1);
if (!d) {
return true;
}
for (int i = 0; i < arr.size();) {
if (arr[i] == m + i * d) {
++i;
} else {
const auto& diff = arr[i] - m;
if (diff % d || diff / d >= arr.size() || arr[i] == arr[diff / d]) {
return false;
}
swap(arr[i], arr[diff / d]);
}
}
return true;
}
};