restructure zeta/** to storage/zeta/**

storage/zeta/py/completed/1874.py

@@ -0,0 +1,22 @@
+def solve(N, I):
+    ret = []
+    stack = []
+    c = 0
+    for i, x in enumerate(I):
+        while c < x:
+            c += 1
+            stack.append(c)
+            ret.append("+")
+
+        if stack[-1] == x:
+            stack.pop()
+            ret.append("-")
+
+        else:
+            return "NO"
+    return "\n".join(ret)
+
+
+if __name__ == '__main__':
+    N = int(input())
+    print(solve(N, list(int(input()) for _ in range(N))))