Fifty-Six Days
The whole campaign at a glance. Two to three hours a day; day seven of every week is rest. Started 2026-06-11 — you are on week 1, day 1.
01
Foundations: arrays, hashing, two pointers
“Slow is smooth, smooth is fast.”
day 1 · todayHow to measure cost
day 2The hash map superpower
day 3Arrays & hashing drills
day 4Two pointers
day 5Two-pointer drills
day 6Week 1 review
02
Windows, stacks, and binary search
“Every O(n²) hides an O(n) trying to get out.”
day 1Sliding window
day 2Stacks & queues
day 3How systems scale (SD #1)
day 4Binary search
day 5Mixed drills
day 6Week 2 review + estimation practice
03
Linked lists and trees
“Draw the pointers. Always draw the pointers.”
day 1Linked lists
day 2Linked-list drills
day 3Design a URL shortener (SD #2)
day 4Trees & BSTs
day 5Tree drills
day 6Week 3 review
04
Traversals, heaps, intervals
“BFS for nearest, DFS for everything.”
day 1Tree BFS & DFS patterns
day 2Heaps & top-k
day 3Design a rate limiter (SD #3)
day 4Intervals
day 5Mixed drills
day 6Week 4 review + first mock
05
Backtracking, graphs, tries
“A graph problem is a traversal problem wearing a costume.”
day 1Backtracking
day 2Graphs: BFS, DFS, topo sort
day 3Design a news feed (SD #4)
day 4Graph drills + union-find
day 5Tries
day 6Design a notification system (SD #5)
06
Greedy and dynamic programming
“DP is recursion with a memory.”
day 1Greedy
day 21-D dynamic programming
day 3Design a chat system (SD #6)
day 41-D DP drills
day 52-D dynamic programming
day 6Week 6 review + mock
07
Hard mixes and big systems
“Pressure is a feature. Train under it.”
day 12-D DP drills
day 2Design video streaming (SD #7)
day 3Mixed hard set + mock
day 4Design a distributed KV store (SD #8)
day 5Weak-area drills
day 6Mock under full pressure
08
Interview week simulation
“You've done the work. Now perform it.”
day 1Mock + review
day 2System design rerun: shortener + rate limiter
day 3Mock + weak areas
day 4System design rerun: feed + chat
day 5Final mock gauntlet
day 6Light review. Sleep.