2020.13. more days setup for that year too

2020/.vscode/tasks.json

@@ -0,0 +1,17 @@
+{
+    // See https://go.microsoft.com/fwlink/?LinkId=733558
+    // for the documentation about the tasks.json format
+    "version": "2.0.0",
+    "tasks": [
+        {
+            "label": "zig build",
+            "type": "shell",
+            "command": "zig build",
+            "problemMatcher": [],
+            "group": {
+                "kind": "build",
+                "isDefault": true
+            }
+        }
+    ]
+}

2020/day13/input.txt

@@ -0,0 +1,9 @@
+19
+37
+383
+23
+13
+29
+457
+41
+17

2020/day13/main.zig

@@ -0,0 +1,47 @@
+const input = @embedFile("input.txt");
+const std = @import("std");
+
+
+pub fn main() !void {
+
+    var it = std.mem.tokenize(u8, input, "\n");
+    var busses:[10]u32 = std.mem.zeroes([10:0]u32);
+    var i: u32 = 0;
+
+    while(it.next())
+        |line|
+        :(i+=1)
+    {
+        busses[i] = (try std.fmt.parseInt(u32, line, 10));
+    }
+
+    std.debug.print("Busses:\n", .{});
+    for(busses)|bus|{
+        std.debug.print("{d}\n", .{bus});
+    }
+
+    const start: u32 = 1000391;
+    var n: u32 = start;
+    var found = false;
+
+
+    while(n > 0 and !found):(n+=1){
+
+        if(n % 1000 == 0)
+            std.debug.print("Tick: {d}\n", .{n});
+        
+        for(busses)|bus|{
+            //skip
+            if(bus == 0){
+                continue;
+            }
+
+            if(n % bus == 0){
+                found = true;
+                std.debug.print("Found! bus {d}, tick {d}, wait {d}, answer {d}\n", .{bus, n, n - start, (n-start)*bus});
+                break;
+            }
+
+        }
+    }
+}