const std = @import("std");

pub fn main() !void {
    var file = try std.fs.cwd().openFile("input.txt", .{});
    defer file.close();

    var a = std.io.bufferedReader(file.reader());
    var readerStream = a.reader();

    var buf: [32]u8 = undefined;
    var top = [3]i32{ 0, 0, 0 };
    var cur: i32 = 0;
    while (try readerStream.readUntilDelimiterOrEof(&buf, '\n')) |line| {
        if (std.mem.eql(u8, line, "")) {
            top[0] = std.math.max(top[0], cur);
            std.sort.sort(i32, &top, {}, std.sort.asc(i32));
            cur = 0;
        } else {
            cur += try std.fmt.parseInt(i32, line, 10);
        }
    }

    var sum: i32 = 0;
    for (top) |val| {
        sum += val;
    }
    std.debug.print("{d}\n", .{sum});
}