diff --git a/input/1.txt b/input/1.txt
new file mode 100644
index 0000000..af23468
--- /dev/null
+++ b/input/1.txt
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diff --git a/runner.d b/runner.d
index cf96109..75851bc 100755
--- a/runner.d
+++ b/runner.d
@@ -1,9 +1,10 @@
-#!/usr/local/bin/rdmd
+#!/usr/bin/rdmd
 
 /**
  * Simple wrapper program for managing the various solutions. Each solution is
- * defined as a single D source file in `src/sX.d`, where `X` is the number of
- * the solution. All executables are placed in a `bin/` directory.
+ * defined as a single D source file in `src/s\d+[a-z]*.d`, which is an "s"
+ * followed by the day number, followed by a character representing which
+ * challenge of the day it is.
  *
  * This script can be executed standalone via `./runner.d`, provided that you
  * have given the script the execution privilege (usually with `chmod +x runner.d`).
@@ -80,7 +81,7 @@ void clean() {
 int run(string[] args) {
     string[] solutionsToRun;
     if (args.length == 0 || args[0].strip().toLower() == "all") {
-        auto r = ctRegex!(`^(s\d+)\.d$`);
+        auto r = ctRegex!(`^(s\d+)[a-z]*\.d$`);
         foreach (entry; dirEntries("src", SpanMode.shallow, false)) {
             auto c = matchFirst(baseName(entry.name), r);
             if (c) solutionsToRun ~= c[1];
@@ -189,10 +190,10 @@ int create(string[] args) {
         return 1;
     }
     string solution = args[0].strip().toLower();
-    auto r = ctRegex!(`^s\d+$`);
+    auto r = ctRegex!(`^s\d+[a-z]*$`);
     auto c = matchFirst(solution, r);
     if (!c) {
-        writefln!"Solution name \"%s\" is not valid. Should be \"s\\d+\"."(solution);
+        writefln!"Solution name \"%s\" is not valid. Should be \"s\\d+[a-z]*\"."(solution);
         return 1;
     }
     string filePath = buildPath("src", solution ~ ".d");
diff --git a/src/s1.d b/src/s1.d
deleted file mode 100644
index a65bf2c..0000000
--- a/src/s1.d
+++ /dev/null
@@ -1,6 +0,0 @@
-module s1;
-import util;
-
-void main() {
-    writeln("Hello world!!");
-}
\ No newline at end of file
diff --git a/src/s1a.d b/src/s1a.d
new file mode 100644
index 0000000..386f006
--- /dev/null
+++ b/src/s1a.d
@@ -0,0 +1,16 @@
+module s1a;
+import util;
+
+void main() {
+    ulong maxCalories = 0;
+    ulong currentCalories = 0;
+    foreach (line; File("input/1.txt", "r").byLine()) {
+        if (line.strip().length == 0) {
+            if (currentCalories > maxCalories) maxCalories = currentCalories;
+            currentCalories = 0;
+        } else {
+            currentCalories += line.strip().to!ulong;
+        }
+    }
+    writeln(maxCalories);
+}
\ No newline at end of file
diff --git a/src/s1b.d b/src/s1b.d
new file mode 100644
index 0000000..bff2d66
--- /dev/null
+++ b/src/s1b.d
@@ -0,0 +1,23 @@
+module s1b;
+import util;
+
+void main() {
+    ulong[] top3 = [0, 0, 0];
+    ulong currentCalories = 0;
+    foreach (line; File("input/1.txt", "r").byLine()) {
+        if (line.strip().length == 0) {
+            for (int i = 0; i < 2; i++) {
+                if (currentCalories > top3[i]) {
+                    // Insert current into the top queue, then trim back to size.
+                    top3 = top3[0 .. i] ~ currentCalories ~ top3[i .. $];
+                    top3 = top3[0 ..3];
+                    break;
+                }
+            }
+            currentCalories = 0;
+        } else {
+            currentCalories += line.strip().to!ulong;
+        }
+    }
+    writeln(top3.sum());
+}