Medium
Jump Game IX — C++
Full explanation · Time O(n) · Space O(1)
// Time: O(n)
// Space: O(1)
// graph, prefix sum
class Solution {
public:
vector<int> maxValue(vector<int>& nums) {
vector<int> result(size(nums));
result[0] = nums[0];
for (int i = 0; i + 1 < size(nums); ++i) {
result[i + 1] = max(result[i], nums[i + 1]);
}
for (int i = size(nums) - 1, mn = numeric_limits<int>::max(); i >= 0; --i) {
if (result[i] > mn) {
result[i] = result[i + 1];
}
mn = min(mn, nums[i]);
}
return result;
}
};
// Time: O(n)
// Space: O(n)
// graph, prefix sum
class Solution2 {
public:
vector<int> maxValue(vector<int>& nums) {
vector<int> suffix(size(nums) + 1, numeric_limits<int>::max());
for (int i = size(nums) - 1; i >= 0; --i) {
suffix[i] = min(suffix[i + 1], nums[i]);
}
vector<int> result(size(nums));
for (int right = 0, left = 0, mx = 0; right < size(nums); ++right) {
mx = max(mx, nums[right]);
if (mx > suffix[right + 1]) {
continue;
}
for (; left <= right; ++left) {
result[left] = mx;
}
}
return result;
}
};