diff --git a/2022/04/both b/2022/04/both
new file mode 100755
index 0000000..08a2380
Binary files /dev/null and b/2022/04/both differ
diff --git a/2022/04/both.nim b/2022/04/both.nim
new file mode 100644
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--- /dev/null
+++ b/2022/04/both.nim
@@ -0,0 +1,41 @@
+import
+  std/strformat,
+  std/strutils
+
+import
+  ../../adventofcode
+
+let input = adventofcode.getInput()
+
+var score = 0
+
+for pair in input.splitLines:
+  let sepIdx = pair.find(',')
+  assert sepIdx != -1
+
+  let range1Str = pair[0 ..< sepIdx]
+  let range2Str = pair[sepIdx + 1 .. ^1]
+  var range1: set[0 .. 65535]
+  var range2: set[0 .. 65535]
+
+  for i in 0 .. 1:
+    let rangeStr = block:
+      if i == 0: range1Str
+      else: range2Str
+    let rangeStrSepIdx = rangeStr.find('-')
+    assert rangeStrSepIdx != -1
+    let rangeStart = parseInt rangeStr[0 ..< rangeStrSepIdx]
+    let rangeEnd = parseInt rangeStr[rangeStrSepIdx + 1 .. ^1]
+    if i == 0: range1 = {rangeStart .. rangeEnd}
+    else: range2 = {rangeStart .. rangeEnd}
+
+  var total = range1 + range2
+  when not defined(second):
+    if range1.len == total.len or range2.len == total.len:
+      score += 1
+  else:
+    if total.len != (range1.len + range2.len):
+      score += 1
+
+echo fmt"Answer: {score}"
+