Data update

Task/Boyer-Moore-string-search/Yabasic/boyer-moore-string-search.basic

@@ -0,0 +1,103 @@
+case_insensitive = false
+
+sub preBmBc(pat$)
+    local m, i
+
+    m = len(pat$)
+    redim bmBc(m)
+    for i = 1 to m-1
+        bmBc(val(mid$(pat$, i, 1))) = m - i
+    next
+end sub
+
+sub suffixes(pat$)
+    local m, g, i, f
+	
+	m = len(pat$)
+    g = m
+    redim suff(m)
+    suff(m) = m
+    for i = m-1 to 1 step -1
+        if i > g and suff(i + m - f) < i - g then
+            suff(i) = suff(i + m - f)
+        else
+            if i < g  g = i
+            f = i
+            while g >= 1 and mid$(pat$, g, 1) = mid$(pat$, g + m - f, 1)
+                g = q - 1
+            wend
+            suff(i) = f - g
+        fi
+    next
+end sub
+
+sub preBmGs(pat$)
+    local m, j, i
+	
+	m = len(pat$)
+    j = 1
+    redim suff(m)
+    redim bmGs(m)
+    for i = m to 1 step -1
+        if suff(i) = i then
+            while j < m - i
+                if bmGs(j) = m  bmGs(j) = m - i
+                j = j + 1
+            wend
+        fi
+    next
+    for i = 1 to m-1
+        bmGs(m - suff(i)) = m - i
+    next
+end sub
+
+sub BM(pat$, s$, case_insensitive)
+    local pins
+
+    pins$ = "'" + pat$ + "' in " + "'" + s$ + "'"
+    if case_insensitive then
+        pat$ = lower$(pat$)
+        s$ = lower$(s$)
+    fi
+
+    //* Preprocessing *//
+    preBmGs(pat$)
+    preBmBc(pat$)
+
+    //* Searching *//
+    j = 0
+	n = len(s$)
+	m = len(pat$)
+	i = m
+
+    while j <= n - m
+        i = i - 1
+        if mid$(pat$,i,1) <> mid$(s$,i+j,1)  break
+
+        if i < 1 then j = j + bmGs(0) else j = j + max(bmGs(i), bmBc(len(mid$(s$,i+j,1)) - m + i)) : fi
+    wend
+
+    many = instr(s$, pat$)
+    tmp$ = ""
+
+    if not many > 0 then
+        print "No ", pins$
+    else
+        while many > 0    //if not found loop will be skipped
+            tmp$ = tmp$ + str$(many) + ","
+            many = instr(s$, pat$, many + 1)
+        wend
+        print "Found ", pins$, " at indices [", tmp$, chr$(8), "]"
+    fi
+end sub
+
+BM("GCAGAGAG","GCATCGCAGAGAGTATACAGTACG")
+BM("TCTA","GCTAGCTCTACGAGTCTA")
+BM("TAATAAA","GGCTATAATGCGTA")
+BM("word","there would have been a time for such a word")
+BM("needle","needle need noodle needle")
+book$ = "InhisbookseriesTheArtofComputerProgrammingpublishedbyAddisonWesleyDKnuthusesanimaginarycomputertheMIXanditsassociatedmachinecodeandassemblylanguagestoillustratetheconceptsandalgorithmsastheyarepresented"
+BM("put",book$)
+BM("and",book$)
+farm$ = "Nearby farms grew a half acre of alfalfa on the dairy's behalf, with bales of all that alfalfa exchanged for milk."
+BM("alfalfa",farm$)