diff --git a/day8/part1/input b/day8/part1/input
new file mode 100644
index 0000000..e49a364
--- /dev/null
+++ b/day8/part1/input
@@ -0,0 +1,625 @@
+jmp +301
+acc +27
+nop +299
+jmp +168
+acc +0
+acc +48
+acc -5
+jmp +420
+jmp +155
+acc -16
+acc -15
+nop +582
+acc -5
+jmp +490
+acc +10
+nop +300
+acc -2
+acc -1
+jmp +252
+jmp +2
+jmp +234
+acc +36
+acc +50
+jmp +564
+jmp +102
+jmp +473
+acc +37
+acc +1
+acc +20
+jmp +355
+acc +28
+acc -14
+acc +22
+jmp +329
+acc +44
+jmp +1
+jmp +23
+nop +312
+jmp +251
+acc +12
+acc +39
+acc +33
+jmp -21
+acc +28
+acc +14
+acc +42
+acc +33
+jmp +502
+jmp +123
+acc +24
+jmp +11
+acc -8
+nop +218
+nop +516
+jmp +244
+jmp -36
+nop +192
+acc -11
+jmp +100
+jmp +299
+jmp +400
+acc +29
+acc +13
+jmp +1
+acc +45
+jmp +458
+acc +6
+acc +15
+jmp +542
+acc +38
+acc -15
+acc -15
+acc -11
+jmp +474
+acc +0
+acc +1
+jmp +55
+acc +14
+acc +13
+acc +37
+acc -18
+jmp +95
+jmp -73
+acc +25
+jmp -54
+jmp +413
+acc -17
+acc +25
+acc +22
+jmp +405
+jmp +151
+jmp +1
+acc -14
+acc +33
+acc +30
+jmp -86
+acc +32
+acc -3
+acc +26
+acc +7
+jmp +493
+acc +44
+jmp +1
+nop +357
+acc +47
+jmp +412
+jmp +321
+acc -5
+jmp +12
+acc +18
+acc -1
+acc +29
+jmp +430
+acc +35
+acc +34
+jmp +1
+acc -6
+jmp +184
+acc -12
+jmp -36
+acc +22
+acc -5
+acc +14
+acc +0
+jmp +198
+jmp +293
+nop +76
+acc +8
+acc +13
+jmp +464
+jmp +309
+acc -19
+acc +27
+acc -10
+jmp +29
+acc -17
+jmp -77
+acc +49
+nop +224
+acc +0
+jmp +77
+acc +35
+acc +3
+jmp +317
+nop +27
+acc +6
+jmp +164
+acc +10
+acc +41
+acc -2
+acc -8
+jmp +347
+acc +14
+nop +148
+jmp +302
+acc +21
+acc +8
+jmp +282
+acc +3
+acc +12
+jmp +138
+acc -10
+jmp +311
+acc -6
+acc -10
+acc +13
+jmp +116
+acc +31
+acc +39
+acc +28
+jmp +244
+nop +59
+acc +16
+jmp +1
+jmp +436
+jmp -31
+acc -12
+acc +43
+jmp -135
+acc -1
+acc +35
+acc +50
+acc +0
+jmp +398
+jmp -83
+acc +40
+acc +26
+acc -8
+jmp +393
+acc +28
+acc -7
+acc +43
+jmp +231
+jmp -22
+acc -1
+acc -18
+acc +19
+jmp -111
+acc +38
+acc +21
+acc +7
+jmp +134
+acc +8
+acc +18
+acc -9
+acc -7
+jmp +24
+acc +5
+acc +0
+jmp -46
+acc +2
+acc -12
+acc -17
+acc +36
+jmp -88
+nop -71
+jmp +181
+jmp -15
+jmp +52
+acc +15
+acc +0
+jmp -32
+acc -6
+nop +166
+acc +10
+acc +38
+jmp +123
+acc +9
+jmp -151
+jmp +231
+jmp +1
+acc +34
+jmp +186
+jmp +96
+acc +48
+acc +9
+jmp +198
+acc +7
+acc +35
+acc +22
+jmp +82
+nop +1
+nop -156
+nop -49
+jmp +91
+acc +8
+acc -17
+jmp -53
+acc +29
+nop +283
+acc -2
+nop +50
+jmp +290
+jmp +296
+jmp +219
+jmp +268
+jmp -119
+nop +353
+jmp -157
+acc +21
+acc +30
+jmp +345
+acc -9
+jmp -119
+acc +0
+jmp -196
+acc +33
+acc +0
+acc +1
+jmp -248
+acc +15
+jmp -44
+acc +9
+acc +46
+acc +50
+jmp +257
+acc -6
+acc -16
+jmp +320
+acc +35
+nop -4
+jmp -5
+acc +30
+acc +27
+jmp +1
+jmp +296
+acc +8
+acc +40
+jmp +210
+acc -14
+acc +34
+acc +42
+jmp +173
+acc +16
+acc +47
+acc +11
+acc +32
+jmp -206
+jmp -39
+acc +45
+jmp +247
+acc -17
+nop +261
+nop -254
+acc +48
+jmp +62
+acc +50
+acc +26
+acc +1
+jmp +130
+acc -14
+nop +47
+acc -9
+jmp -276
+jmp -104
+jmp +135
+acc +40
+jmp -296
+jmp +11
+acc +2
+acc -17
+jmp -238
+acc +34
+acc +37
+jmp -166
+nop -205
+acc -4
+acc +22
+jmp +56
+acc +1
+nop -210
+nop -30
+acc -18
+jmp -250
+jmp -107
+acc +45
+acc +50
+acc +3
+acc +3
+jmp -63
+acc +35
+jmp +1
+acc -5
+nop +255
+jmp +254
+jmp +210
+acc +10
+acc +7
+jmp +207
+acc +17
+acc +25
+nop -22
+jmp +62
+acc +35
+acc +18
+acc +22
+acc +10
+jmp -186
+acc +24
+acc +32
+jmp -31
+jmp -131
+jmp -337
+acc +41
+acc -10
+acc +42
+jmp +207
+acc -16
+acc -14
+nop -225
+acc -15
+jmp +70
+nop -303
+acc -10
+acc +11
+acc +17
+jmp +234
+acc -8
+acc +33
+jmp -131
+acc -9
+acc -12
+acc +31
+jmp -25
+nop -277
+acc +22
+jmp -273
+acc +19
+jmp -244
+acc -8
+nop +220
+acc +48
+jmp -261
+acc +23
+acc +11
+acc -16
+jmp -47
+acc +50
+acc -9
+acc +23
+jmp -38
+jmp +146
+nop -168
+jmp -88
+acc +37
+acc +36
+acc +43
+acc -7
+jmp +147
+jmp +1
+acc +42
+jmp -352
+acc +39
+jmp +76
+acc +47
+jmp +88
+acc -2
+jmp -102
+acc +20
+jmp +144
+acc +47
+acc +25
+jmp -55
+nop -65
+jmp -375
+acc +8
+jmp +161
+acc +46
+acc +5
+acc +16
+jmp +53
+acc +27
+acc +1
+jmp -6
+jmp -207
+acc -6
+acc +27
+nop +126
+jmp -197
+jmp -110
+jmp +123
+acc +13
+acc +31
+nop +22
+acc +41
+jmp -127
+acc -7
+nop -386
+acc +0
+jmp -65
+jmp -306
+acc +44
+acc +19
+acc +42
+acc +29
+jmp +92
+acc +42
+nop -156
+jmp -56
+jmp -346
+nop +95
+acc -6
+acc -19
+jmp -292
+jmp -443
+acc -12
+acc -18
+jmp +102
+nop +35
+acc +44
+acc +27
+nop -122
+jmp +97
+jmp -382
+jmp -85
+acc -9
+nop -324
+jmp -422
+acc -9
+acc +25
+acc +38
+acc -3
+jmp -298
+acc -2
+acc +26
+acc +14
+jmp -252
+acc +4
+jmp +75
+acc +17
+nop -208
+jmp -235
+acc +19
+jmp -322
+acc +14
+acc -3
+jmp +124
+jmp -221
+jmp -9
+acc +0
+acc +45
+acc -3
+jmp -376
+acc +20
+acc -3
+acc +17
+acc +19
+jmp -400
+acc -16
+acc +25
+jmp -37
+jmp -317
+acc +31
+acc +19
+acc +24
+acc +9
+jmp -181
+acc +35
+jmp -488
+acc -13
+acc +26
+acc -2
+jmp -338
+acc -1
+acc +17
+acc +44
+nop -262
+jmp -86
+acc +17
+acc -1
+acc +23
+jmp +79
+acc -5
+acc +18
+jmp +1
+acc +12
+jmp -127
+acc +1
+acc +35
+acc -10
+acc +14
+jmp -352
+acc +39
+nop +67
+jmp -290
+acc -13
+jmp +41
+jmp -150
+jmp -121
+acc +7
+jmp -331
+acc +42
+nop -389
+acc +4
+jmp -7
+acc -17
+acc -8
+acc -4
+jmp -209
+acc +42
+acc +39
+acc +43
+jmp -306
+acc -18
+acc -16
+acc +13
+jmp -414
+acc +3
+jmp -442
+nop +41
+acc -12
+jmp -194
+jmp -503
+acc -18
+acc +35
+acc -4
+acc +18
+jmp -393
+nop -348
+acc -7
+jmp -521
+acc +48
+acc -19
+acc -3
+acc +44
+jmp +2
+jmp -126
+nop -474
+acc -9
+acc -2
+acc +35
+jmp -587
+jmp -328
+acc -14
+nop -468
+acc +39
+jmp -157
+jmp -538
+acc +0
+nop -264
+acc +19
+nop -266
+jmp -91
+acc +20
+acc +14
+jmp -329
+acc -11
+acc +8
+jmp -219
+jmp -320
+acc +10
+acc +49
+nop -603
+acc +49
+jmp -344
+nop -356
+nop -93
+acc +27
+acc +24
+jmp -482
+nop -126
+nop -345
+acc +6
+acc +3
+jmp +1
diff --git a/day8/part1/main.d b/day8/part1/main.d
new file mode 100644
index 0000000..9b60319
--- /dev/null
+++ b/day8/part1/main.d
@@ -0,0 +1,50 @@
+import std;
+
+void main()
+{
+    "input".slurp!(string, int)("%s %s").executeProgramAndReturnAcc.writeln;
+}
+
+alias Instruction = Tuple!(string, int);
+alias Program = Instruction[];
+
+auto executeProgramAndReturnAcc(Program program)
+{
+    int accumulator;
+    // dfmt off
+    alias operation = void delegate(ref ulong ip, int arg);
+    operation[string] operations = [
+        "nop" : (scope ref size_t ip, int arg) {ip += 1;},
+        "acc" : (scope ref size_t ip, int arg) { accumulator += arg; ip += 1; },
+        "jmp" : (scope ref size_t ip, int arg) {ip += arg;}
+    ];
+    // dfmt on
+    void[0][size_t] seenIPs;
+    size_t ip = 0;
+    while (ip !in seenIPs)
+    {
+        seenIPs[ip] = [];
+        operations[program[ip][0]](ip, program[ip][1]);
+    }
+    return accumulator;
+}
+
+unittest
+{
+    auto program = `nop +0
+acc +1
+jmp +4
+acc +3
+jmp -3
+acc -99
+acc +1
+jmp -4
+acc +6`.splitter("\n").filter!(not!empty)
+        .map!((line) {
+            auto opAndArg = line.split(" ");
+            return tuple(opAndArg[0], opAndArg[1].to!int);
+        })
+        .array;
+
+    assert(program.executeProgramAndReturnAcc == 5);
+}
diff --git a/day8/part2/input b/day8/part2/input
new file mode 100644
index 0000000..e49a364
--- /dev/null
+++ b/day8/part2/input
@@ -0,0 +1,625 @@
+jmp +301
+acc +27
+nop +299
+jmp +168
+acc +0
+acc +48
+acc -5
+jmp +420
+jmp +155
+acc -16
+acc -15
+nop +582
+acc -5
+jmp +490
+acc +10
+nop +300
+acc -2
+acc -1
+jmp +252
+jmp +2
+jmp +234
+acc +36
+acc +50
+jmp +564
+jmp +102
+jmp +473
+acc +37
+acc +1
+acc +20
+jmp +355
+acc +28
+acc -14
+acc +22
+jmp +329
+acc +44
+jmp +1
+jmp +23
+nop +312
+jmp +251
+acc +12
+acc +39
+acc +33
+jmp -21
+acc +28
+acc +14
+acc +42
+acc +33
+jmp +502
+jmp +123
+acc +24
+jmp +11
+acc -8
+nop +218
+nop +516
+jmp +244
+jmp -36
+nop +192
+acc -11
+jmp +100
+jmp +299
+jmp +400
+acc +29
+acc +13
+jmp +1
+acc +45
+jmp +458
+acc +6
+acc +15
+jmp +542
+acc +38
+acc -15
+acc -15
+acc -11
+jmp +474
+acc +0
+acc +1
+jmp +55
+acc +14
+acc +13
+acc +37
+acc -18
+jmp +95
+jmp -73
+acc +25
+jmp -54
+jmp +413
+acc -17
+acc +25
+acc +22
+jmp +405
+jmp +151
+jmp +1
+acc -14
+acc +33
+acc +30
+jmp -86
+acc +32
+acc -3
+acc +26
+acc +7
+jmp +493
+acc +44
+jmp +1
+nop +357
+acc +47
+jmp +412
+jmp +321
+acc -5
+jmp +12
+acc +18
+acc -1
+acc +29
+jmp +430
+acc +35
+acc +34
+jmp +1
+acc -6
+jmp +184
+acc -12
+jmp -36
+acc +22
+acc -5
+acc +14
+acc +0
+jmp +198
+jmp +293
+nop +76
+acc +8
+acc +13
+jmp +464
+jmp +309
+acc -19
+acc +27
+acc -10
+jmp +29
+acc -17
+jmp -77
+acc +49
+nop +224
+acc +0
+jmp +77
+acc +35
+acc +3
+jmp +317
+nop +27
+acc +6
+jmp +164
+acc +10
+acc +41
+acc -2
+acc -8
+jmp +347
+acc +14
+nop +148
+jmp +302
+acc +21
+acc +8
+jmp +282
+acc +3
+acc +12
+jmp +138
+acc -10
+jmp +311
+acc -6
+acc -10
+acc +13
+jmp +116
+acc +31
+acc +39
+acc +28
+jmp +244
+nop +59
+acc +16
+jmp +1
+jmp +436
+jmp -31
+acc -12
+acc +43
+jmp -135
+acc -1
+acc +35
+acc +50
+acc +0
+jmp +398
+jmp -83
+acc +40
+acc +26
+acc -8
+jmp +393
+acc +28
+acc -7
+acc +43
+jmp +231
+jmp -22
+acc -1
+acc -18
+acc +19
+jmp -111
+acc +38
+acc +21
+acc +7
+jmp +134
+acc +8
+acc +18
+acc -9
+acc -7
+jmp +24
+acc +5
+acc +0
+jmp -46
+acc +2
+acc -12
+acc -17
+acc +36
+jmp -88
+nop -71
+jmp +181
+jmp -15
+jmp +52
+acc +15
+acc +0
+jmp -32
+acc -6
+nop +166
+acc +10
+acc +38
+jmp +123
+acc +9
+jmp -151
+jmp +231
+jmp +1
+acc +34
+jmp +186
+jmp +96
+acc +48
+acc +9
+jmp +198
+acc +7
+acc +35
+acc +22
+jmp +82
+nop +1
+nop -156
+nop -49
+jmp +91
+acc +8
+acc -17
+jmp -53
+acc +29
+nop +283
+acc -2
+nop +50
+jmp +290
+jmp +296
+jmp +219
+jmp +268
+jmp -119
+nop +353
+jmp -157
+acc +21
+acc +30
+jmp +345
+acc -9
+jmp -119
+acc +0
+jmp -196
+acc +33
+acc +0
+acc +1
+jmp -248
+acc +15
+jmp -44
+acc +9
+acc +46
+acc +50
+jmp +257
+acc -6
+acc -16
+jmp +320
+acc +35
+nop -4
+jmp -5
+acc +30
+acc +27
+jmp +1
+jmp +296
+acc +8
+acc +40
+jmp +210
+acc -14
+acc +34
+acc +42
+jmp +173
+acc +16
+acc +47
+acc +11
+acc +32
+jmp -206
+jmp -39
+acc +45
+jmp +247
+acc -17
+nop +261
+nop -254
+acc +48
+jmp +62
+acc +50
+acc +26
+acc +1
+jmp +130
+acc -14
+nop +47
+acc -9
+jmp -276
+jmp -104
+jmp +135
+acc +40
+jmp -296
+jmp +11
+acc +2
+acc -17
+jmp -238
+acc +34
+acc +37
+jmp -166
+nop -205
+acc -4
+acc +22
+jmp +56
+acc +1
+nop -210
+nop -30
+acc -18
+jmp -250
+jmp -107
+acc +45
+acc +50
+acc +3
+acc +3
+jmp -63
+acc +35
+jmp +1
+acc -5
+nop +255
+jmp +254
+jmp +210
+acc +10
+acc +7
+jmp +207
+acc +17
+acc +25
+nop -22
+jmp +62
+acc +35
+acc +18
+acc +22
+acc +10
+jmp -186
+acc +24
+acc +32
+jmp -31
+jmp -131
+jmp -337
+acc +41
+acc -10
+acc +42
+jmp +207
+acc -16
+acc -14
+nop -225
+acc -15
+jmp +70
+nop -303
+acc -10
+acc +11
+acc +17
+jmp +234
+acc -8
+acc +33
+jmp -131
+acc -9
+acc -12
+acc +31
+jmp -25
+nop -277
+acc +22
+jmp -273
+acc +19
+jmp -244
+acc -8
+nop +220
+acc +48
+jmp -261
+acc +23
+acc +11
+acc -16
+jmp -47
+acc +50
+acc -9
+acc +23
+jmp -38
+jmp +146
+nop -168
+jmp -88
+acc +37
+acc +36
+acc +43
+acc -7
+jmp +147
+jmp +1
+acc +42
+jmp -352
+acc +39
+jmp +76
+acc +47
+jmp +88
+acc -2
+jmp -102
+acc +20
+jmp +144
+acc +47
+acc +25
+jmp -55
+nop -65
+jmp -375
+acc +8
+jmp +161
+acc +46
+acc +5
+acc +16
+jmp +53
+acc +27
+acc +1
+jmp -6
+jmp -207
+acc -6
+acc +27
+nop +126
+jmp -197
+jmp -110
+jmp +123
+acc +13
+acc +31
+nop +22
+acc +41
+jmp -127
+acc -7
+nop -386
+acc +0
+jmp -65
+jmp -306
+acc +44
+acc +19
+acc +42
+acc +29
+jmp +92
+acc +42
+nop -156
+jmp -56
+jmp -346
+nop +95
+acc -6
+acc -19
+jmp -292
+jmp -443
+acc -12
+acc -18
+jmp +102
+nop +35
+acc +44
+acc +27
+nop -122
+jmp +97
+jmp -382
+jmp -85
+acc -9
+nop -324
+jmp -422
+acc -9
+acc +25
+acc +38
+acc -3
+jmp -298
+acc -2
+acc +26
+acc +14
+jmp -252
+acc +4
+jmp +75
+acc +17
+nop -208
+jmp -235
+acc +19
+jmp -322
+acc +14
+acc -3
+jmp +124
+jmp -221
+jmp -9
+acc +0
+acc +45
+acc -3
+jmp -376
+acc +20
+acc -3
+acc +17
+acc +19
+jmp -400
+acc -16
+acc +25
+jmp -37
+jmp -317
+acc +31
+acc +19
+acc +24
+acc +9
+jmp -181
+acc +35
+jmp -488
+acc -13
+acc +26
+acc -2
+jmp -338
+acc -1
+acc +17
+acc +44
+nop -262
+jmp -86
+acc +17
+acc -1
+acc +23
+jmp +79
+acc -5
+acc +18
+jmp +1
+acc +12
+jmp -127
+acc +1
+acc +35
+acc -10
+acc +14
+jmp -352
+acc +39
+nop +67
+jmp -290
+acc -13
+jmp +41
+jmp -150
+jmp -121
+acc +7
+jmp -331
+acc +42
+nop -389
+acc +4
+jmp -7
+acc -17
+acc -8
+acc -4
+jmp -209
+acc +42
+acc +39
+acc +43
+jmp -306
+acc -18
+acc -16
+acc +13
+jmp -414
+acc +3
+jmp -442
+nop +41
+acc -12
+jmp -194
+jmp -503
+acc -18
+acc +35
+acc -4
+acc +18
+jmp -393
+nop -348
+acc -7
+jmp -521
+acc +48
+acc -19
+acc -3
+acc +44
+jmp +2
+jmp -126
+nop -474
+acc -9
+acc -2
+acc +35
+jmp -587
+jmp -328
+acc -14
+nop -468
+acc +39
+jmp -157
+jmp -538
+acc +0
+nop -264
+acc +19
+nop -266
+jmp -91
+acc +20
+acc +14
+jmp -329
+acc -11
+acc +8
+jmp -219
+jmp -320
+acc +10
+acc +49
+nop -603
+acc +49
+jmp -344
+nop -356
+nop -93
+acc +27
+acc +24
+jmp -482
+nop -126
+nop -345
+acc +6
+acc +3
+jmp +1
diff --git a/day8/part2/main.d b/day8/part2/main.d
new file mode 100644
index 0000000..fc94deb
--- /dev/null
+++ b/day8/part2/main.d
@@ -0,0 +1,89 @@
+import std;
+
+void main()
+{
+    "input".slurp!(string, int)("%s %s").fixProgramAndReturnAcc[0].writeln;
+}
+
+alias Instruction = Tuple!(string, int);
+alias Program = Instruction[];
+
+auto executeProgramAndReturnAcc(Program program)
+{
+    int accumulator;
+    // dfmt off
+    alias operation = void delegate(ref ulong ip, int arg);
+    operation[string] operations = [
+        "nop" : (scope ref size_t ip, int arg) {ip += 1;},
+        "acc" : (scope ref size_t ip, int arg) { accumulator += arg; ip += 1; },
+        "jmp" : (scope ref size_t ip, int arg) {ip += arg;}
+    ];
+    // dfmt on
+    void[0][size_t] seenIPs;
+    size_t ip = 0;
+    while (ip !in seenIPs && ip < program.length)
+    {
+        seenIPs[ip] = [];
+        operations[program[ip][0]](ip, program[ip][1]);
+    }
+    return tuple(accumulator, ip == program.length);
+}
+
+auto fixProgramAndReturnAcc(Program program)
+{
+    return program.enumerate
+        .map!((indexedInstruction) {
+            if (indexedInstruction.value[0] == "acc")
+                return tuple(0, false);
+            else if (indexedInstruction.value[0] == "nop")
+                indexedInstruction.value[0] = "jmp";
+            else
+                indexedInstruction.value[0] = "nop";
+
+            return (program[0 .. indexedInstruction.index]
+                ~ [indexedInstruction.value] ~ program[indexedInstruction.index + 1 .. $])
+                .executeProgramAndReturnAcc;
+        })
+        .find!(result => result[1])
+        .front;
+}
+
+unittest
+{
+    auto program = `nop +0
+acc +1
+jmp +4
+acc +3
+jmp -3
+acc -99
+acc +1
+jmp -4
+acc +6`.splitter("\n").filter!(not!empty)
+        .map!((line) {
+            auto opAndArg = line.split(" ");
+            return tuple(opAndArg[0], opAndArg[1].to!int);
+        })
+        .array;
+
+    assert(program.executeProgramAndReturnAcc == tuple(5, false));
+}
+
+unittest
+{
+    auto program = `nop +0
+acc +1
+jmp +4
+acc +3
+jmp -3
+acc -99
+acc +1
+jmp -4
+acc +6`.splitter("\n").filter!(not!empty)
+        .map!((line) {
+            auto opAndArg = line.split(" ");
+            return tuple(opAndArg[0], opAndArg[1].to!int);
+        })
+        .array;
+
+    assert(program.fixProgramAndReturnAcc == tuple(8, true));
+}