create dev channel

zeta/py/completed/11509_faster.py

@@ -0,0 +1,13 @@
+def solve(N, H):
+    arrow = [0] * 1000001
+    for h in H:
+        if arrow[h]:
+            arrow[h] -= 1
+        arrow[h - 1] += 1
+    return sum(arrow)
+
+
+if __name__ == '__main__':
+    N = int(input())
+    H = list(map(int, input().split()))
+    print(solve(N, H))