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const std = @import("std");
const day7 = @import("day7");
pub fn main() !void {
// Initiate allocator
var gpa = std.heap.GeneralPurposeAllocator(.{}){};
defer _ = gpa.deinit();
const alloc = gpa.allocator();
// Read contents from file "./filename"
const cwd = std.fs.cwd();
const fileContents = try cwd.readFileAlloc(alloc, "day7.txt", 24000);
defer alloc.free(fileContents);
// Print file contents
// std.debug.print("{s}", .{fileContents});
var lines = std.mem.splitScalar(u8, fileContents, '\n');
const firstLine = lines.first();
const startPos = std.mem.indexOf(u8, firstLine, "S") orelse unreachable;
var positions = try std.array_list.Aligned(u64, null).initCapacity(alloc, firstLine.len);
defer positions.deinit(alloc);
try positions.resize(alloc, firstLine.len);
@memset(positions.items, 0);
positions.items[startPos] = 1;
while (lines.next()) |line| {
for (line, 0..) |value, i| {
const position_value = positions.items[i];
if (value == '^' and position_value > 0) {
// do left
positions.items[i - 1] += position_value;
// right
positions.items[i + 1] += position_value;
positions.items[i] -= position_value;
}
}
std.debug.print("{}\n", .{positions});
}
var final_result: u64 = 0;
for (positions.items) |i| {
final_result += i;
}
std.debug.print("result: {}\n", .{final_result});
try day7.bufferedPrint();
}
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