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--- Part Two ---
"Good, the new computer seems to be working correctly! [1m[97mKeep it nearby[0m during this mission - you'll
probably use it again. Real Intcode computers support many more features than your new one, but
we'll let you know what they are as you need them."
"However, your current priority should be to complete your gravity assist around the Moon. For this
mission to succeed, we should settle on some terminology for the parts you've already built."
Intcode programs are given as a list of integers; these values are used as the initial state for the
computer's [1m[97mmemory[0m. When you run an Intcode program, make sure to start by initializing memory to the
program's values. A position in memory is called an [1m[97maddress[0m (for example, the first value in memory
is at "address 0").
Opcodes (like 1, 2, or 99) mark the beginning of an [1m[97minstruction[0m. The values used immediately after
an opcode, if any, are called the instruction's [1m[97mparameters[0m. For example, in the instruction
1,2,3,4, 1 is the opcode; 2, 3, and 4 are the parameters. The instruction 99 contains only an opcode
and has no parameters.
The address of the current instruction is called the [1m[97minstruction pointer[0m; it starts at 0. After an
instruction finishes, the instruction pointer increases by [1m[97mthe number of values in the
instruction[0m; until you add more instructions to the computer, this is always 4 (1 opcode + 3
parameters) for the add and multiply instructions. (The halt instruction would increase the
instruction pointer by 1, but it halts the program instead.)
"With terminology out of the way, we're ready to proceed. To complete the gravity assist, you need
to [1m[97mdetermine what pair of inputs produces the output 19690720[0m."
The inputs should still be provided to the program by replacing the values at addresses 1 and 2,
just like before. In this program, the value placed in address 1 is called the [1m[97mnoun[0m, and the value
placed in address 2 is called the [1m[97mverb[0m. Each of the two input values will be between 0 and 99,
inclusive.
Once the program has halted, its output is available at address 0, also just like before. Each time
you try a pair of inputs, make sure you first [1m[97mreset the computer's memory to the values in the
program[0m (your puzzle input) - in other words, don't reuse memory from a previous attempt.
Find the input [1m[97mnoun[0m and [1m[97mverb[0m that cause the program to produce the output 19690720. [1m[97mWhat is 100 *
noun + verb?[0m (For example, if noun=12 and verb=2, the answer would be 1202.)
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