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Currently Playing: Xah Ep721 Wolfram Language, Advent of Code 2025, Day 1, Problem 2

Video Summary (Generated by AI, Edited by Human.) This video shows the process of solving Advent of Code 2025 Day 1 Problem 2 using Wolfram Language. The creator explains the problem, which involves calculating the number of times a dial on a rotational lock points at zero, whether it stops there or passes by during rotation (3:23). They attempt to model the lock's behavior using modular arithmetic to track the current position and the number of times zero is passed. The creator writes a function to compute this, testing it with examples (36:27). The video then goes through multiple debugging attempts, addressing edge cases like starting or ending at zero, and issues with sign conventions for left and right rotations (1:11:08). Despite extensive debugging, they face continued challenges in getting the correct answer for the full input, leading to the session concluding with the problem still unsolved (3:00:28). Notes at http://xahlee.info/talk_show/xah_talk_show_ep721.html If browser says security error, that is because it auto changes URL from HTTP to HTTPS. It's a way to censor 22 million old websites. Remove the S in HTTPS. Or use brave browser or safari.