diff --git a/day21/input.txt b/day21/input.txt
new file mode 100644
index 0000000..97c3f9d
--- /dev/null
+++ b/day21/input.txt
@@ -0,0 +1,100 @@
+move position 0 to position 3
+rotate right 0 steps
+rotate right 1 step
+move position 1 to position 5
+swap letter h with letter b
+reverse positions 1 through 3
+swap letter a with letter g
+swap letter b with letter h
+rotate based on position of letter c
+swap letter d with letter c
+rotate based on position of letter c
+swap position 6 with position 5
+rotate right 7 steps
+swap letter b with letter h
+move position 4 to position 3
+swap position 1 with position 0
+swap position 7 with position 5
+move position 7 to position 1
+swap letter c with letter a
+move position 7 to position 5
+rotate right 4 steps
+swap position 0 with position 5
+move position 3 to position 1
+swap letter c with letter h
+rotate based on position of letter d
+reverse positions 0 through 2
+rotate based on position of letter g
+move position 6 to position 7
+move position 2 to position 5
+swap position 1 with position 0
+swap letter f with letter c
+rotate right 1 step
+reverse positions 2 through 4
+rotate left 1 step
+rotate based on position of letter h
+rotate right 1 step
+rotate right 5 steps
+swap position 6 with position 3
+move position 0 to position 5
+swap letter g with letter f
+reverse positions 2 through 7
+reverse positions 4 through 6
+swap position 4 with position 1
+move position 2 to position 1
+move position 3 to position 1
+swap letter b with letter a
+rotate based on position of letter b
+reverse positions 3 through 5
+move position 0 to position 2
+rotate based on position of letter b
+reverse positions 4 through 5
+rotate based on position of letter g
+reverse positions 0 through 5
+swap letter h with letter c
+reverse positions 2 through 5
+swap position 7 with position 5
+swap letter g with letter d
+swap letter d with letter e
+move position 1 to position 2
+move position 3 to position 2
+swap letter d with letter g
+swap position 3 with position 7
+swap letter b with letter f
+rotate right 3 steps
+move position 5 to position 3
+move position 1 to position 2
+rotate based on position of letter b
+rotate based on position of letter c
+reverse positions 2 through 3
+move position 2 to position 3
+rotate right 1 step
+move position 7 to position 0
+rotate right 3 steps
+move position 6 to position 3
+rotate based on position of letter e
+swap letter c with letter b
+swap letter f with letter d
+swap position 2 with position 5
+swap letter f with letter g
+rotate based on position of letter a
+reverse positions 3 through 4
+rotate left 7 steps
+rotate left 6 steps
+swap letter g with letter b
+reverse positions 3 through 6
+rotate right 6 steps
+rotate based on position of letter c
+rotate based on position of letter b
+rotate left 1 step
+reverse positions 3 through 7
+swap letter f with letter g
+swap position 4 with position 1
+rotate based on position of letter d
+move position 0 to position 4
+swap position 7 with position 6
+rotate right 6 steps
+rotate based on position of letter e
+move position 7 to position 3
+rotate right 3 steps
+swap position 1 with position 2
diff --git a/day21/part1.js b/day21/part1.js
new file mode 100644
index 0000000..80ebece
--- /dev/null
+++ b/day21/part1.js
@@ -0,0 +1,32 @@
+swapPos = (str, a, b)=>{
+	str = str.split("");
+	temp = str[a];
+	str[a] = str[b];
+	str[b] = temp;
+	return str.join("");
+};
+swapLetter = (str, a, b) => (str.split("").map((char)=>((char == a) ? (b) : ((char == b) ? (a) : (char)))).join(""));
+rotate = (str, steps) => (str.split("").map((a, i)=>(str[(i + steps + str.length)%(str.length)])).join("")); //left pos, right neg
+rotatePos = (str, char) => (str.split("").map((a, i)=>(str[(i - str.indexOf(char) - ((str.indexOf(char) >= 4) ? (2) : (1)) + (str.length*2))%(str.length)])).join(""));
+reverseBetween = (str, a, b) => (str.split("").map((char, i)=>(((i >= a) && (i <= b)) ? (str[b - (i - a)]) : (char))).join(""));
+moveToPos = (str, a, b) => {
+	var str = str.split("");
+	var char = str.splice(a, 1)[0];
+	str.splice(b, 0, char);
+	return str.join("");
+};
+
+var input = require("fs").readFileSync("input.txt").toString().replace(/\r/g, "");
+var instructions = input.split("\n").filter((a)=>(a)).map((str)=>(
+	str
+	.replace(/swap position ([0-9]+) with position ([0-9]+)/g, "swapPos(text, $1, $2)")
+	.replace(/swap letter (.) with letter (.)/g, "swapLetter(text, \"$1\", \"$2\")")
+	.replace(/rotate left ([0-9]+) step(s)?/g, "rotate(text, $1)")
+	.replace(/rotate right ([0-9]+) step(s)?/g, "rotate(text, -$1)")
+	.replace(/rotate based on position of letter (.)/g, "rotatePos(text, \"$1\")")
+	.replace(/reverse positions ([0-9]+) through ([0-9]+)/g, "reverseBetween(text, $1, $2)")
+	.replace(/move position ([0-9]+) to position ([0-9]+)/g, "moveToPos(text, $1, $2)")
+));
+
+var out = instructions.reduce((text, instruction)=>(eval(instruction)), "abcdefgh")
+console.log(out);
diff --git a/day21/part2.js b/day21/part2.js
new file mode 100644
index 0000000..b886370
--- /dev/null
+++ b/day21/part2.js
@@ -0,0 +1,32 @@
+swapPos = (str, a, b)=>{
+	str = str.split("");
+	temp = str[a];
+	str[a] = str[b];
+	str[b] = temp;
+	return str.join("");
+};
+swapLetter = (str, a, b) => (str.split("").map((char)=>((char == a) ? (b) : ((char == b) ? (a) : (char)))).join(""));
+rotate = (str, steps) => (str.split("").map((a, i)=>(str[(i + steps + str.length)%(str.length)])).join("")); //left pos, right neg
+reverseRotatePos = (str, char) => (str.split("").map((a, i)=>(str[(i + ((str.indexOf(char)%2 == 0) ? (/*even*/ (((str.indexOf(char) == 0) ? (str.length) : (str.indexOf(char)))/2) + 5) : (/*odd*/ Math.ceil((str.indexOf(char))/2))) + (str.length*2))%(str.length)])).join(""));
+reverseBetween = (str, a, b) => (str.split("").map((char, i)=>(((i >= a) && (i <= b)) ? (str[b - (i - a)]) : (char))).join(""));
+moveToPos = (str, a, b) => {
+	var str = str.split("");
+	var char = str.splice(a, 1)[0];
+	str.splice(b, 0, char);
+	return str.join("");
+};
+
+var input = require("fs").readFileSync("input.txt").toString().replace(/\r/g, "");
+var instructions = input.split("\n").reverse().filter((a)=>(a)).map((str)=>(
+	str
+	.replace(/swap position ([0-9]+) with position ([0-9]+)/g, "swapPos(text, $1, $2)")
+	.replace(/swap letter (.) with letter (.)/g, "swapLetter(text, \"$1\", \"$2\")")
+	.replace(/rotate left ([0-9]+) step(s)?/g, "rotate(text, -$1)")
+	.replace(/rotate right ([0-9]+) step(s)?/g, "rotate(text, $1)")
+	.replace(/rotate based on position of letter (.)/g, "reverseRotatePos(text, \"$1\")")
+	.replace(/reverse positions ([0-9]+) through ([0-9]+)/g, "reverseBetween(text, $1, $2)")
+	.replace(/move position ([0-9]+) to position ([0-9]+)/g, "moveToPos(text, $2, $1)")
+));
+
+var out = instructions.reduce((text, instruction)=>(eval(instruction)), "fbgdceah")
+console.log(out);