Data commit

Task/Longest-common-substring/Nim/longest-common-substring.nim

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+# Longest common substring.
+
+import sequtils
+
+func lcs(a, b: string): string =
+  var lengths = newSeqWith(a.len, newSeq[int](b.len))
+  var greatestLength = 0
+  for i, x in a:
+    for j, y in b:
+      if x == y:
+        lengths[i][j] = if i == 0 or j == 0: 1 else: lengths[i - 1][j - 1] + 1
+        if lengths[i][j] > greatestLength:
+          greatestLength = lengths[i][j]
+          result = a[(i - greatestLength + 1)..i]
+
+echo lcs("thisisatest", "testing123testing")