added writeups exported from ctfnote

Random-Password-crypto.md

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+# Random Password - crypto
+
+
+```
+def backtrack(idx, sample, fives, sevens, accu, result):
+    if idx == 5718 and len(result(256)):
+        result.append(accu)
+        return
+
+    if len(fives) > 1 and sum(fives) < 5:
+        fives.append(sample[idx])
+        backtrack(idx + 1, sample,fives, sevens, accu, result)
+        fives.pop()
+    elif len(sevens) > 1 and sum(sevens) < 17:
+        sevens.append(sample[idx])
+        backtrack(idx + 1, sample,fives, sevens, accu, result)
+        sevens.pop()
+    elif len(fives) > 1 and sum(fives) > 5:r
+	accu.append(fives)
+        backtrack(idx, sample, [], sevens, accu, result)
+	accu.pop()
+    elif len(sevens) > 1 and sum(sevens) > 17:
+	accu.append(sevens)
+        backtrack(idx, sample, fives, [], accu, result)
+	accu.pop()
+
+    fives.append(sample[idx])
+    backtrack(idx + 1, sample,fives, sevens, accu, result)
+    fives.pop()
+
+    sevens.append(sample[idx])
+    backtrack(idx + 1, sample,fives, sevens, accu, result)
+    sevens.pop()
+
+result = []
+backtrack(0, sample, [], [], [], result)
+
+```