1 files changed, 38 insertions, 0 deletions
diff --git a/store/works/life/2020-algorithm-contest/code/3.cpp b/store/works/life/2020-algorithm-contest/code/3.cpp
new file mode 100644
index 0000000..088cc5e
--- /dev/null
+++ b/store/works/life/2020-algorithm-contest/code/3.cpp
@@ -0,0 +1,38 @@
+#include <iostream>
+
+int main()
+{
+    int length, numRows;
+    std::cin >> length >> numRows;
+
+    if (numRows == 1)
+    {
+        for (int i = 1; i <= length; i++)
+            std::cout << i << ' ';
+        return 0;
+    }
+
+    const int count_per_group = numRows * 2 - 2;
+    for (int row = 0; row < numRows; row++)
+    {
+        if (row == 0)
+        {
+            for (int p = 0; p < length; p += count_per_group)
+                std::cout << p + 1 << ' ';
+        }
+        else if (row == numRows - 1)
+        {
+            for (int p = row; p < length; p += count_per_group)
+                std::cout << p + 1 << ' ';
+        }
+        else
+        {
+            bool former = true;
+            const auto former_gap = count_per_group - row * 2;
+            const auto latter_gap = count_per_group - former_gap;
+            for (int p = row; p < length; p += (former ? former_gap : latter_gap), former = !former)
+                std::cout << p + 1 << ' ';
+        }
+    }
+    return 0;
+}