LeetCode

LeetCode 1486 note: generate start + 2i by definition and XOR them together

LeetCode 2469 note: apply the formulas directly, Kelvin = C + 273.15 and Fahrenheit = C × 1.8 + 32

LeetCode 2413 note: lcm(2, n), which is n when n is even and 2n when odd

LeetCode 2236 note: a warm-up, plus practice with C++ pointer access

LeetCode 2235 note: return the sum; the C++ version once failed to compile from a missing semicolon

LeetCode 3750 note: compare the binary string with its reverse bit by bit; the number of mismatches is the answer

LeetCode 3731 note: the minimum and maximum are still present, so check every integer in between against a set

LeetCode 3712 note: count each value, and for counts divisible by k add value × count

LeetCode 3709 note: times are increasing, so store prefix sums and answer queries with two bisects; always parenthesize mid

LeetCode 3708 note: lengths 1 and 2 always work; from the third element, extend while nums[i] == nums[i-1] + nums[i-2], otherwise reset to 2

LeetCode 3707 note: accumulate the left score while scanning, with the right side as total minus left; scores are alphabet positions 1 to 26, not ord

LeetCode 394 note: on [ push the current string and count, on ] pop and combine; counts can have several digits