summaryrefslogtreecommitdiff
path: root/leetcode/cpp/746.cpp
diff options
context:
space:
mode:
authorcrupest <crupest@outlook.com>2021-02-23 21:07:19 +0800
committercrupest <crupest@outlook.com>2021-02-23 21:07:19 +0800
commitd8f3b40085619cb680c8f227c65a1f5acc393223 (patch)
tree6a38e3a6c79276fc396259ef962d17236dbed569 /leetcode/cpp/746.cpp
parentb0162802ad9723c678e495f29ca2f0fc0af2eff1 (diff)
downloadsolutions-d8f3b40085619cb680c8f227c65a1f5acc393223.tar.gz
solutions-d8f3b40085619cb680c8f227c65a1f5acc393223.tar.bz2
solutions-d8f3b40085619cb680c8f227c65a1f5acc393223.zip
Move leetcode solutions to subdir.
Diffstat (limited to 'leetcode/cpp/746.cpp')
-rw-r--r--leetcode/cpp/746.cpp35
1 files changed, 35 insertions, 0 deletions
diff --git a/leetcode/cpp/746.cpp b/leetcode/cpp/746.cpp
new file mode 100644
index 0000000..72ffd9f
--- /dev/null
+++ b/leetcode/cpp/746.cpp
@@ -0,0 +1,35 @@
+#include <vector>
+
+using std::vector;
+
+#include <algorithm>
+
+class Solution
+{
+public:
+ int minCostClimbingStairs(vector<int> &cost)
+ {
+ int count = cost.size();
+
+ // Total cost for index i means min cost of stepping through the number i stair,
+ // after which you are free to jump two or one stair.
+ // total_costs[i] is based on total_costs[i - 2] and total_costs[i - 1].
+ // Note:
+ // This is not min cost to step above the number i stair, which has no simple dependency
+ // relationship because based on whether it steps through the last step there are two situation.
+ // However with the restriction of stepping through that last stair, there is a
+ // dependency relationship. And we can easily get the final result by comparing total_costs[count - 2]
+ // and total_costs[count - 1]. But not just use total_costs[count - 1].
+ vector<int> total_costs(count);
+
+ total_costs[0] = cost[0];
+ total_costs[1] = cost[1];
+
+ for (int i = 2; i < count; i++)
+ {
+ total_costs[i] = std::min(total_costs[i - 2], total_costs[i - 1]) + cost[i];
+ }
+
+ return std::min(total_costs[count - 2], total_costs[count - 1]);
+ }
+};