diff --git a/day-1/makefile b/day-1/makefile
index 5a0aa8d..d1bbae3 100644
--- a/day-1/makefile
+++ b/day-1/makefile
@@ -2,9 +2,9 @@ TEST="test.txt"
 INPUT="input.txt"
 
 test:
-	cat $(TEST) | go run .
+	go run . < $(TEST)
 
 run:
-	cat $(INPUT) | go run .
+	go run . < $(INPUT)
 
 all: test
diff --git a/day-10/makefile b/day-10/makefile
index 5a0aa8d..d1bbae3 100644
--- a/day-10/makefile
+++ b/day-10/makefile
@@ -2,9 +2,9 @@ TEST="test.txt"
 INPUT="input.txt"
 
 test:
-	cat $(TEST) | go run .
+	go run . < $(TEST)
 
 run:
-	cat $(INPUT) | go run .
+	go run . < $(INPUT)
 
 all: test
diff --git a/day-11/makefile b/day-11/makefile
index 5a0aa8d..d1bbae3 100644
--- a/day-11/makefile
+++ b/day-11/makefile
@@ -2,9 +2,9 @@ TEST="test.txt"
 INPUT="input.txt"
 
 test:
-	cat $(TEST) | go run .
+	go run . < $(TEST)
 
 run:
-	cat $(INPUT) | go run .
+	go run . < $(INPUT)
 
 all: test
diff --git a/day-12/makefile b/day-12/makefile
index 680ef75..a1b81fb 100644
--- a/day-12/makefile
+++ b/day-12/makefile
@@ -2,9 +2,9 @@ TEST="test.txt"
 INPUT="input.txt"
 
 test:
-	cat $(TEST) | go run .
+	go run . < $(TEST)
 
 run:
-	cat $(INPUT) | go run .
+	go run . < $(INPUT)
 
 all: test
\ No newline at end of file
diff --git a/day-13/makefile b/day-13/makefile
index 680ef75..a1b81fb 100644
--- a/day-13/makefile
+++ b/day-13/makefile
@@ -2,9 +2,9 @@ TEST="test.txt"
 INPUT="input.txt"
 
 test:
-	cat $(TEST) | go run .
+	go run . < $(TEST)
 
 run:
-	cat $(INPUT) | go run .
+	go run . < $(INPUT)
 
 all: test
\ No newline at end of file
diff --git a/day-14/makefile b/day-14/makefile
index 5a0aa8d..d1bbae3 100644
--- a/day-14/makefile
+++ b/day-14/makefile
@@ -2,9 +2,9 @@ TEST="test.txt"
 INPUT="input.txt"
 
 test:
-	cat $(TEST) | go run .
+	go run . < $(TEST)
 
 run:
-	cat $(INPUT) | go run .
+	go run . < $(INPUT)
 
 all: test
diff --git a/day-15/makefile b/day-15/makefile
index 5a0aa8d..d1bbae3 100644
--- a/day-15/makefile
+++ b/day-15/makefile
@@ -2,9 +2,9 @@ TEST="test.txt"
 INPUT="input.txt"
 
 test:
-	cat $(TEST) | go run .
+	go run . < $(TEST)
 
 run:
-	cat $(INPUT) | go run .
+	go run . < $(INPUT)
 
 all: test
diff --git a/day-16/makefile b/day-16/makefile
index 5a0aa8d..d1bbae3 100644
--- a/day-16/makefile
+++ b/day-16/makefile
@@ -2,9 +2,9 @@ TEST="test.txt"
 INPUT="input.txt"
 
 test:
-	cat $(TEST) | go run .
+	go run . < $(TEST)
 
 run:
-	cat $(INPUT) | go run .
+	go run . < $(INPUT)
 
 all: test
diff --git a/day-2/makefile b/day-2/makefile
index 5a0aa8d..d1bbae3 100644
--- a/day-2/makefile
+++ b/day-2/makefile
@@ -2,9 +2,9 @@ TEST="test.txt"
 INPUT="input.txt"
 
 test:
-	cat $(TEST) | go run .
+	go run . < $(TEST)
 
 run:
-	cat $(INPUT) | go run .
+	go run . < $(INPUT)
 
 all: test
diff --git a/day-3/makefile b/day-3/makefile
index 5a0aa8d..d1bbae3 100644
--- a/day-3/makefile
+++ b/day-3/makefile
@@ -2,9 +2,9 @@ TEST="test.txt"
 INPUT="input.txt"
 
 test:
-	cat $(TEST) | go run .
+	go run . < $(TEST)
 
 run:
-	cat $(INPUT) | go run .
+	go run . < $(INPUT)
 
 all: test
diff --git a/day-4/makefile b/day-4/makefile
index 5a0aa8d..d1bbae3 100644
--- a/day-4/makefile
+++ b/day-4/makefile
@@ -2,9 +2,9 @@ TEST="test.txt"
 INPUT="input.txt"
 
 test:
-	cat $(TEST) | go run .
+	go run . < $(TEST)
 
 run:
-	cat $(INPUT) | go run .
+	go run . < $(INPUT)
 
 all: test
diff --git a/day-5/makefile b/day-5/makefile
index 5a0aa8d..d1bbae3 100644
--- a/day-5/makefile
+++ b/day-5/makefile
@@ -2,9 +2,9 @@ TEST="test.txt"
 INPUT="input.txt"
 
 test:
-	cat $(TEST) | go run .
+	go run . < $(TEST)
 
 run:
-	cat $(INPUT) | go run .
+	go run . < $(INPUT)
 
 all: test
diff --git a/day-6/makefile b/day-6/makefile
index 5a0aa8d..d1bbae3 100644
--- a/day-6/makefile
+++ b/day-6/makefile
@@ -2,9 +2,9 @@ TEST="test.txt"
 INPUT="input.txt"
 
 test:
-	cat $(TEST) | go run .
+	go run . < $(TEST)
 
 run:
-	cat $(INPUT) | go run .
+	go run . < $(INPUT)
 
 all: test
diff --git a/day-7/makefile b/day-7/makefile
index 5a0aa8d..d1bbae3 100644
--- a/day-7/makefile
+++ b/day-7/makefile
@@ -2,9 +2,9 @@ TEST="test.txt"
 INPUT="input.txt"
 
 test:
-	cat $(TEST) | go run .
+	go run . < $(TEST)
 
 run:
-	cat $(INPUT) | go run .
+	go run . < $(INPUT)
 
 all: test
diff --git a/day-8/makefile b/day-8/makefile
index 5a0aa8d..d1bbae3 100644
--- a/day-8/makefile
+++ b/day-8/makefile
@@ -2,9 +2,9 @@ TEST="test.txt"
 INPUT="input.txt"
 
 test:
-	cat $(TEST) | go run .
+	go run . < $(TEST)
 
 run:
-	cat $(INPUT) | go run .
+	go run . < $(INPUT)
 
 all: test
diff --git a/day-9/makefile b/day-9/makefile
index 5a0aa8d..d1bbae3 100644
--- a/day-9/makefile
+++ b/day-9/makefile
@@ -2,9 +2,9 @@ TEST="test.txt"
 INPUT="input.txt"
 
 test:
-	cat $(TEST) | go run .
+	go run . < $(TEST)
 
 run:
-	cat $(INPUT) | go run .
+	go run . < $(INPUT)
 
 all: test