diff --git a/main.cc b/main.cc
index 474ffab..25b08a5 100644
--- a/main.cc
+++ b/main.cc
@@ -11,6 +11,7 @@
 #include <string_view>
 #include <vector>
 #include <iostream>
+#include <set>
 
 /** (x, y) pair storing a position. */
 using Pos = std::pair<int, int>;
@@ -76,35 +77,9 @@ struct Grid {
 
   /** Add a square to the grid. */
   auto add(Square const &sq) noexcept -> void {
-    switch (sq.length()) {
-      case 1: set(sq.x(), sq.y(), '*');
-        break;
-      case 2: set(sq.x(), sq.y(), '+');
-        set(sq.x() + 1, sq.y(), '+');
-        set(sq.x(), sq.y() + 1, '+');
-        set(sq.x() + 1, sq.y() + 1, '+');
-        break;
-      default: {
-        auto n = sq.length();
-        set(sq.x(), sq.y(), '+');
-        set(sq.x() + n - 1, sq.y(), '+');
-        set(sq.x(), sq.y() + n - 1, '+');
-        set(sq.x() + n - 1, sq.y() + n - 1, '+');
-        for (int i = 1; i < n - 1; ++i) {
-          set(sq.x() + i, sq.y(), '-');
-          set(sq.x() + i, sq.y() + n - 1, '-');
-          set(sq.x(), sq.y() + i, '|');
-          for (int j = 1; j < n - 1; ++j) {
-            set(sq.x() + j, sq.y() + i, ' ');
-          }
-          set(sq.x() + n - 1, sq.y() + i, '|');
-        }
-
-        int i = sq.x() + n - 1;
-        while (n != 0) {
-          set(--i, sq.y() + 1, '0' + (n % 10));
-          n /= 10;
-        }
+    for (auto i = sq.x(); i < sq.x() + sq.length(); ++i) {
+      for (auto j = sq.y(); j < sq.y() + sq.length(); ++j) {
+        set(i, j, sq.length());
       }
     }
   }
@@ -118,6 +93,15 @@ struct Grid {
     }
   }
 
+  auto prettify() noexcept -> void {
+    for (auto idx = 0; idx < grid_.size(); ++idx) {
+      if (grid_[idx] < 32) {
+        auto const pos = std::make_pair(idx % length_, idx / length_);
+        prettify_sq(Square(pos, grid_[idx]));
+      }
+    }
+  }
+
   /** Output the grid. */
   auto output() const -> void {
     for (auto idx = 0; idx < length_ * length_; idx += length_) {
@@ -162,6 +146,40 @@ struct Grid {
   }
 
 private:
+  auto prettify_sq(Square const &sq) noexcept -> void {
+    switch (sq.length()) {
+      case 1: set(sq.x(), sq.y(), '*');
+        break;
+      case 2: set(sq.x(), sq.y(), '+');
+        set(sq.x() + 1, sq.y(), '+');
+        set(sq.x(), sq.y() + 1, '+');
+        set(sq.x() + 1, sq.y() + 1, '+');
+        break;
+      default: {
+        auto n = sq.length();
+        set(sq.x(), sq.y(), '+');
+        set(sq.x() + n - 1, sq.y(), '+');
+        set(sq.x(), sq.y() + n - 1, '+');
+        set(sq.x() + n - 1, sq.y() + n - 1, '+');
+        for (int i = 1; i < n - 1; ++i) {
+          set(sq.x() + i, sq.y(), '-');
+          set(sq.x() + i, sq.y() + n - 1, '-');
+          set(sq.x(), sq.y() + i, '|');
+          for (int j = 1; j < n - 1; ++j) {
+            set(sq.x() + j, sq.y() + i, ' ');
+          }
+          set(sq.x() + n - 1, sq.y() + i, '|');
+        }
+
+        int i = sq.x() + n - 1;
+        while (n != 0) {
+          set(--i, sq.y() + 1, '0' + (n % 10));
+          n /= 10;
+        }
+      }
+    }
+  }
+
   /** Set the grid position (x, y) to the character c.
    *
    * It is an error if (x, y) is already set to c - as that means we have overlapping
@@ -229,6 +247,7 @@ auto find_solution(int n) -> Grid {
   Avail avail_sqs;
   for (auto i = 0; i <= n; ++i) { avail_sqs.push_back(i); }
   find_solution_impl(grid, n, std::make_pair(0, 0), avail_sqs);
+  grid.prettify();
   return grid;
 }