diff --git a/test/day2.in b/test/day2.in
new file mode 100644
index 0000000..05eb9af
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+2-4 d: dmclzdvdd
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+1-3 p: ptpzpqlhprvxhrgvvgv
+4-7 n: nnnvnnnn
+5-6 c: plnccqrxtxcwzkccm
+5-10 j: jjjjjjjjjr
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+7-10 t: wtttthtttthvt
+2-7 m: mrmfmjgcpmmmbwx
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+2-3 c: ctcc
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+5-7 x: xxxwxxp
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+3-7 w: whfdzvwpg
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+4-9 g: gggggggglg
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+8-11 w: lwwwwwwwwjw
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+3-8 z: vhzgnkzgkcqrmmvvkx
+7-11 n: nnnnnnnnnnmnn
+1-15 b: bbbftxndbbfbbpb
+6-7 d: wkdddldldcddddd
+3-5 b: bcbfvbd
+9-10 k: kkkkkqkkrk
+8-18 z: vszwbmgzjzgjmhpgcv
+4-9 z: zzzzznczxz
+3-4 d: dhdm
+1-9 q: zqqqqqgcqqq
+2-3 g: zvgnx
+2-4 j: jqjjh
+6-11 j: hcqcnjqjjgj
+5-6 j: jjjjjj
+6-7 d: dwdddkd
+1-5 l: pmplllll
+1-11 t: tttdlttsrpkqtt
+3-9 x: xxnxtxxxx
+7-8 f: fffffffg
+4-6 b: bhbbbrhbb
+6-11 f: xfncmzffrfsf
+10-11 h: pghprtcjjjhshkw
+8-10 n: nnknnnnznnnn
+3-5 q: jqqqk
+5-9 j: rrhfgjfjjjjjbdjnj
+6-8 t: tctjmtttqttt
+9-10 m: wmvmhmmmxddzmmmm
+2-11 c: flcqrnrqmcccs
+2-3 f: qfdx
+11-15 k: kkkkdkkkkkgkkkkkkrq
+9-14 h: hzhhfhhxhhhhhltnh
diff --git a/test/day2.krk b/test/day2.krk
new file mode 100644
index 0000000..d2a0a2e
--- /dev/null
+++ b/test/day2.krk
@@ -0,0 +1,34 @@
+from fileio import open
+let f = open('test/day2.in')
+let lines = f.read().split('\n')[:-1]
+
+def check_first(policy_low, policy_high, letter, password):
+    let count = 0
+    for l in password:
+        if l == letter:
+            count += 1
+    return count >= policy_low and count <= policy_high
+
+def check_second(policy_low, policy_high, letter, password):
+    let count = 0
+    if password[policy_low-1] == letter:
+        count += 1
+    if password[policy_high-1] == letter:
+        count += 1
+    return count == 1
+
+let valid = 0
+for line in lines:
+    let s = line.split(': ',1)
+    let password = s[1]
+    let policy = s[0]
+    s = policy.split('-',1)
+    let policy_low = int(s[0])
+    s = s[1].split(' ',1)
+    let policy_high = int(s[0])
+    let letter = s[1]
+    let is_valid = check_second(policy_low, policy_high, letter, password)
+    print policy_low, policy_high, letter, password, is_valid
+    if is_valid:
+        valid += 1
+print valid
diff --git a/vm.c b/vm.c
index e621317..75c0ef2 100644
--- a/vm.c
+++ b/vm.c
@@ -1926,6 +1926,63 @@ static KrkValue _repr(int argc, KrkValue argv[]) {
 	return krk_callSimple(krk_peek(0), 0, 1);
 }
 
+static KrkValue _striter_init(int argc, KrkValue argv[]) {
+	if (!IS_INSTANCE(argv[0]) || AS_INSTANCE(argv[0])->_class != vm.baseClasses.striteratorClass) {
+		krk_runtimeError(vm.exceptions.typeError, "Tried to call striterator.__init__() on something not a str iterator");
+	}
+	if (argc < 2 || !IS_STRING(argv[1])) {
+		krk_runtimeError(vm.exceptions.argumentError, "Expected a str.");
+	}
+	KrkInstance * self = AS_INSTANCE(argv[0]);
+
+	krk_push(argv[0]);
+	krk_attachNamedValue(&self->fields, "s", argv[1]);
+	krk_attachNamedValue(&self->fields, "i", INTEGER_VAL(0));
+	krk_pop();
+
+	return argv[0];
+}
+
+static KrkValue _striter_call(int argc, KrkValue argv[]) {
+	if (!IS_INSTANCE(argv[0]) || AS_INSTANCE(argv[0])->_class != vm.baseClasses.striteratorClass) {
+		krk_runtimeError(vm.exceptions.typeError, "Tried to call striterator.__call__() on something not a str iterator");
+	}
+	KrkInstance * self = AS_INSTANCE(argv[0]);
+	KrkValue _str;
+	KrkValue _counter;
+	const char * errorStr = NULL;
+
+	if (!krk_tableGet(&self->fields, OBJECT_VAL(S("s")), &_str)) {
+		errorStr = "no str pointer";
+		goto _corrupt;
+	}
+	if (!krk_tableGet(&self->fields, OBJECT_VAL(S("i")), &_counter)) {
+		errorStr = "no index";
+		goto _corrupt;
+	}
+
+	if ((size_t)AS_INTEGER(_counter) >= AS_STRING(_str)->length) {
+		return argv[0];
+	} else {
+		krk_attachNamedValue(&self->fields, "i", INTEGER_VAL(AS_INTEGER(_counter)+1));
+		return OBJECT_VAL(krk_copyString(&AS_CSTRING(_str)[AS_INTEGER(_counter)],1));
+	}
+
+_corrupt:
+	krk_runtimeError(vm.exceptions.typeError, "Corrupt str iterator: %s", errorStr);
+	return NONE_VAL();
+}
+
+static KrkValue _str_iter(int argc, KrkValue argv[]) {
+	KrkInstance * output = krk_newInstance(vm.baseClasses.striteratorClass);
+
+	krk_push(OBJECT_VAL(output));
+	_striter_init(3, (KrkValue[]){krk_peek(0), argv[0]});
+	krk_pop();
+
+	return OBJECT_VAL(output);
+}
+
 static KrkValue _listiter_init(int argc, KrkValue argv[]) {
 	if (!IS_INSTANCE(argv[0]) || AS_INSTANCE(argv[0])->_class != vm.baseClasses.listiteratorClass) {
 		krk_runtimeError(vm.exceptions.typeError, "Tried to call listiterator.__init__() on something not a list iterator");
@@ -2172,6 +2229,7 @@ void krk_initVM(int flags) {
 	krk_defineNative(&vm.baseClasses.strClass->methods, ".__getslice__", _string_get_slice);
 	krk_defineNative(&vm.baseClasses.strClass->methods, ".__ord__", _char_to_int);
 	krk_defineNative(&vm.baseClasses.strClass->methods, ".__contains__", _string_contains);
+	krk_defineNative(&vm.baseClasses.strClass->methods, ".__iter__", _str_iter);
 	krk_defineNative(&vm.baseClasses.strClass->methods, ".format", _string_format);
 	krk_defineNative(&vm.baseClasses.strClass->methods, ".join", _string_join);
 	krk_defineNative(&vm.baseClasses.strClass->methods, ".split", _string_split);
@@ -2204,6 +2262,10 @@ void krk_initVM(int flags) {
 	krk_defineNative(&vm.baseClasses.listiteratorClass->methods, ".__init__", _listiter_init);
 	krk_defineNative(&vm.baseClasses.listiteratorClass->methods, ".__call__", _listiter_call);
 
+	ADD_BASE_CLASS(vm.baseClasses.striteratorClass, "striterator", vm.objectClass);
+	krk_defineNative(&vm.baseClasses.striteratorClass->methods, ".__init__", _striter_init);
+	krk_defineNative(&vm.baseClasses.striteratorClass->methods, ".__call__", _striter_call);
+
 	ADD_BASE_CLASS(vm.baseClasses.rangeClass, "range", vm.objectClass);
 	krk_attachNamedObject(&vm.globals, "range", (KrkObj*)vm.baseClasses.rangeClass);
 	krk_defineNative(&vm.baseClasses.rangeClass->methods, ".__init__", _range_init);
diff --git a/vm.h b/vm.h
index 7e588cb..c23bf96 100644
--- a/vm.h
+++ b/vm.h
@@ -90,6 +90,7 @@ typedef struct {
 		KrkClass * listiteratorClass;
 		KrkClass * rangeClass;
 		KrkClass * rangeiteratorClass;
+		KrkClass * striteratorClass;
 	} baseClasses;
 
 	KrkValue currentException;