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Add day 14 part 2 after fighting with longs and bishifting

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Chris Josten 2020-12-14 08:42:21 +01:00
parent 8a5bbcefdc
commit d02f0ce415
Signed by: chris
GPG key ID: 1795A594046530AB
1 changed files with 98 additions and 29 deletions
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127
source/day14.d
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@ -1,3 +1,4 @@
import std.bitmanip;
import std.conv;
import dayutil;
@ -87,27 +88,27 @@ long part1(Instruction[] instructions) {
Value[] bitmask;
long[long] memory;
foreach(instruction; instructions) {
final switch(instruction.op) {
case Operation.WRITE_BITMASK:
bitmask = instruction.value;
break;
case Operation.WRITE_MEM:
Value[] tmp = instruction.value;
foreach(ref bit, mask; lockstep(tmp.retro, bitmask.retro)) {
final switch(mask) {
case Value.ZERO:
bit = Value.ZERO;
break;
case Value.ONE:
bit = Value.ONE;
break;
case Value.X: break;
final switch(instruction.op) {
case Operation.WRITE_BITMASK:
bitmask = instruction.value;
break;
case Operation.WRITE_MEM:
Value[] tmp = instruction.value;
foreach(ref bit, mask; lockstep(tmp.retro, bitmask.retro)) {
final switch(mask) {
case Value.ZERO:
bit = Value.ZERO;
break;
case Value.ONE:
bit = Value.ONE;
break;
case Value.X: break;
}
}
}
//writeln(tmp);
memory[instruction.address] = fromStupidBinary(tmp);
break;
}
//writeln(tmp);
memory[instruction.address] = fromStupidBinary(tmp);
break;
}
}
long sum = 0;
foreach(e; memory.byValue()) {
@ -117,20 +118,88 @@ long part1(Instruction[] instructions) {
return sum;
}
int part2(Range)(Range range) if (isInputRange!Range) {
return 0;
}
unittest {
string input = q"EOS
string input = q"EOS
mask = XXXXXXXXXXXXXXXXXXXXXXXXXXXXX1XXXX0X
mem[8] = 11
mem[7] = 101
mem[8] = 0
EOS";
auto parsed = parseInput(input.lineSplitter);
writeln(parsed);
writeln(part1(parsed.save));
assert(part1(parsed.save) == 165);
assert(part1(parsed) == 165);
}
long[] addressPermutations(Value[] address) {
import std.math;
long[] addresses;
addresses ~= [0];
addresses.reserve(pow(2, addresses.count(Value.X)));
foreach(idx, bit; address.retro.enumerate) {
if (bit == Value.X) {
auto duplicate = addresses.dup;
foreach(ref address2; duplicate) {
address2 += (cast(long) 1 << idx);
}
addresses ~= duplicate;
} else if (bit == Value.ONE) {
foreach(ref address2; addresses) {
address2 += (cast(long) 1 << idx);
}
}
}
writeln(address);
foreach(address2; addresses) {
writeln("Address: %064b".format(address2));
}
assert(addresses.length == pow(2, address.count(Value.X)));
assert(addresses.uniq.array.length == addresses.length);
return addresses;
}
long part2(Instruction[] instructions) {
Value[] bitmask;
long[long] memory;
foreach(instruction; instructions) {
final switch(instruction.op) {
case Operation.WRITE_BITMASK:
bitmask = instruction.value;
break;
case Operation.WRITE_MEM:
Value[] tmp = toStupidBinary(instruction.address);
foreach(ref bit, mask; lockstep(tmp, bitmask)) {
final switch(mask) {
case Value.ZERO: break;
case Value.ONE:
bit = Value.ONE;
break;
case Value.X:
bit = Value.X;
break;
}
}
//writeln(tmp);
foreach(long address; addressPermutations(tmp)) {
//writeln("Writing to address ", address);
memory[address] = fromStupidBinary(instruction.value);
}
break;
}
}
return memory.byValue().sum;
}
unittest {
string input = q"EOS
mask = 000000000000000000000000000000X1001X
mem[42] = 100
mask = 00000000000000000000000000000000X0XX
mem[26] = 1
EOS";
auto parsed = parseInput(input.lineSplitter);
writeln(parsed);
assert(part2(parsed) == 208);
}