diff --git a/test.sh b/test.sh
index e64af44..492c116 100755
--- a/test.sh
+++ b/test.sh
@@ -11,6 +11,9 @@ OUTDIR=$(mktemp --directory)
 trap "rm -rf '$OUTDIR'" EXIT
 
 run_solution() {
+	local solution=$1
+	local input=$2
+
 	if [[ -d "$solution" ]]; then
 		if [[ -f "$solution/Cargo.toml" ]]; then
 			cargo run --quiet --manifest-path "$solution/Cargo.toml" < "$input"
@@ -36,11 +39,11 @@ run_solution() {
 }
 
 do_day() {
-	year=$1
-	day=$2
+	local year=$1
+	local day=$2
 
-	input=$year/data/day$day.input
-	expected=$year/data/day$day.expected
+	local input=$year/data/day$day.input
+	local expected=$year/data/day$day.expected
 
 	for solution in "$year/day$day"/*; do
 		echo -n "$solution... "
@@ -54,8 +57,8 @@ do_day() {
 				;;
 		esac
 
-		solution_output=$OUTDIR/${year}_$day.out
-		run_solution "$solution" > "$solution_output"
+		local solution_output=$OUTDIR/${year}_$day.out
+		run_solution "$solution" "$input" > "$solution_output"
 
 		if ! diff -u "$expected" "$solution_output"; then
 			echo FAIL
@@ -75,7 +78,7 @@ do_day() {
 }
 
 do_year() {
-	year=$1
+	local year=$1
 
 	for day in $(seq 1 25); do
 		do_day "$year" "$day"