add new task

practica/stepik/stepik_tasks/index_of_num_in_list.py

@@ -0,0 +1,15 @@
+lst = input().split()
+x = int(input())
+n= 0
+list_n= []
+while n < len(lst):
+    for i in lst:
+        m = int(i)
+        if m ==x:
+            list_n.append(n)
+            n+=1
+        else: 
+            n+=1
+    if len(list_n) == 0:
+        print ('Отсутствует')
+print(" ".join(map(str, list_n)))