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const std = @import("std");
const day5 = @import("day5");
const Range = struct {
start: u64,
end: u64,
};
fn isFresh(ranges: *std.array_list.Aligned, value: u64) bool {
for (ranges.*.items) |r| {
if (r.start <= value and value <= r.end) {
return true;
}
}
return false;
}
fn lessThenByStart(_: void, a: Range, b: Range) bool {
return a.start < b.start; // ascending
}
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, "day5.txt", 24000);
defer alloc.free(fileContents);
// Print file contents
// std.debug.print("{s}", .{fileContents});
var lines = std.mem.splitScalar(u8, fileContents, '\n');
var fresh: u64 = 0;
var fresh_ranges = std.array_list.Aligned(Range, null).empty;
defer fresh_ranges.deinit(alloc);
while (lines.next()) |row| {
if (row.len == 0) { // break between ranges and values
break;
}
var r = std.mem.splitScalar(u8, row, '-');
const sStr = r.next() orelse unreachable;
const eStr = r.next() orelse unreachable;
const s: u64 = try std.fmt.parseInt(u64, sStr, 10);
const e: u64 = try std.fmt.parseInt(u64, eStr, 10);
try fresh_ranges.append(alloc, Range{ .start = s, .end = e });
}
std.sort.block(Range, fresh_ranges.items, {}, lessThenByStart);
var real_ranges = std.array_list.Aligned(Range, null).empty;
defer real_ranges.deinit(alloc);
const first_ele = fresh_ranges.items[0];
var current_start = first_ele.start;
var current_end = first_ele.end;
for (fresh_ranges.items) |fr| {
const start = fr.start;
const end = fr.end;
if (start <= current_end) {
current_end = @max(current_end, end);
continue;
} else {
try real_ranges.append(alloc, Range{ .start = current_start, .end = current_end });
current_end = end;
current_start = start;
}
}
try real_ranges.append(alloc, Range{ .start = current_start, .end = current_end });
for (real_ranges.items) |rr| {
std.debug.print("start:{}, end:{}\n", .{ rr.start, rr.end });
fresh += rr.end - rr.start + 1;
}
std.debug.print("fresh: {}\n", .{fresh});
try day5.bufferedPrint();
}
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