leetcode

5 Database Problems

6 files changed, 28 insertions(+), 0 deletions(-)

diff --git a/ Problems/0596.sql b/ Problems/0596.sql

@@ -0,0 +1,4 @@

SELECT class

FROM Courses

GROUP BY class

HAVING COUNT(DISTINCT student) >= 5

diff --git a/ Problems/0619.sql b/ Problems/0619.sql

@@ -0,0 +1,7 @@

SELECT MAX(num) AS num

FROM (

SELECT num

FROM MyNUmbers

GROUP BY num

HAVING COUNT(num) = 1

) AS unique_num

diff --git a/ Problems/1141.sql b/ Problems/1141.sql

@@ -0,0 +1,5 @@

SELECT activity_date AS day,

COUNT(DISTINCT user_id) AS active_users

FROM Activity

WHERE activity_date BETWEEN '2019-06-28' AND '2019-07-27'

GROUP BY activity_date

diff --git a/ Problems/1729.sql b/ Problems/1729.sql

@@ -0,0 +1,4 @@

SELECT user_id, COUNT(follower_id) AS followers_count

FROM Followers

GROUP BY user_id

ORDER BY user_id ASC

diff --git a/ Problems/2356.sql b/ Problems/2356.sql

@@ -0,0 +1,3 @@

SELECT teacher_id, COUNT(DISTINCT subject_ID) AS cnt

FROM Teacher

GROUP BY teacher_id

diff --git a/ README.md b/ README.md

@@ -358,10 +358,12 @@ for solving problems. | 0589 | Easy | [N-ary Tree Preorder Traversal](Problems/0589.cpp) | | 0590 | Easy | [N-ary Tree Postorder Traversal](Problems/0590.cpp) | | 0595 | Easy | [Big Countries](Problems/0595.cpp) |

| 0596 | Easy | [Classes More Than 5 Students](Problems/0596.cpp) |

| 0605 | Easy | [Can Place Flowers](Problems/0605.cpp) | | 0606 | Easy | [Construct String from Binary Tree ](Problems/0606.cpp) | | 0609 | Medium | [Find Duplicate File in System](Problems/0609.cpp) | | 0617 | Easy | [Merge Two Binary Trees](Problems/0617.cpp) |

| 0619 | Easy | [Biggest Single Number](Problems/0619.cpp) |

| 0620 | Easy | [Not Boring Movies](Problems/0620.cpp) | | 0621 | Medium | [Task Scheduler](Problems/0621.cpp) | | 0623 | Medium | [Add One Row to Tree](Problems/0623.cpp) |

@@ -552,6 +554,7 @@ for solving problems. | 1130 | Medium | [Minimum Cost Tree From Leaf Values](Problems/1130.cpp) | | 1137 | Easy | [N-th Tribonacci Number](Problems/1137.cpp) | | 1140 | Medium | [Stone Game II](Problems/1140.cpp) |

| 1141 | Easy | [User Activity for the Past 30 Days I](Problems/1141.cpp) |

| 1143 | Medium | [Longest Common Subsequence](Problems/1143.cpp) | | 1146 | Medium | [Snapshot Array](Problems/1146.cpp) | | 1148 | Easy | [Article Views I](Problems/1148.cpp) |

@@ -744,6 +747,7 @@ for solving problems. | 1722 | Medium | [Minimize Hamming Distance After Swap Operations](Problems/1722.cpp) | | 1726 | Medium | [Tuple with Same Product](Problems/1726.cpp) | | 1727 | Medium | [Largest Submatrix With Rearrangements](Problems/1727.cpp) |

| 1729 | Easy | [Find Followers Count](Problems/1729.cpp) |

| 1732 | Easy | [Find the Highest Altitude](Problems/1732.cpp) | | 1734 | Medium | [Decode XORed Permutation](Problems/1734.cpp) | | 1738 | Medium | [Find Kth Largest XOR Coordinate Value](Problems/1738.cpp) |

@@ -868,6 +872,7 @@ for solving problems. | 2343 | Medium | [Query Kth Smallest Trimmed Number](Problems/2343.cpp) | | 2348 | Medium | [Number of Zero-Filled Subarrays](Problems/2348.cpp) | | 2352 | Medium | [Equal Row and Column Pairs](Problems/2352.cpp) |

| 2356 | Easy | [Number of Unique Subjects Taught by Each Teacher](Problems/2356.cpp) |

| 2358 | Medium | [Maximum Number of Groups Entering a Competition](Problems/2358.cpp) | | 2359 | Medium | [Find Closest Node to Given Two Nodes](Problems/2359.cpp) | | 2360 | Hard | [Longest Cycle in a Graph](Problems/2360.cpp) |