Data commit

Task/Knapsack-problem-0-1/LSL/knapsack-problem-0-1-1.lsl

@@ -0,0 +1,50 @@
+string sNOTECARD = "Knapsack_Problem_0_1_Data.txt";
+integer iMAX_WEIGHT = 400;
+integer iSTRIDE = 4;
+list lList = [];
+default {
+	integer iNotecardLine = 0;
+	state_entry() {
+		llOwnerSay("Reading '"+sNOTECARD+"'");
+		llGetNotecardLine(sNOTECARD, iNotecardLine);
+	}
+	dataserver(key kRequestId, string sData) {
+		if(sData==EOF) {
+			//llOwnerSay("EOF");
+			lList = llListSort(lList, iSTRIDE, FALSE);
+			integer iTotalWeight = 0;
+			integer iTotalValue = 0;
+			list lKnapsack = [];
+			integer x = 0;
+			while(x*iSTRIDE<llGetListLength(lList)) {
+				float fValueWeight = (float)llList2String(lList, x*iSTRIDE);
+				string sItem = (string)llList2String(lList, x*iSTRIDE+1);
+				integer iWeight = (integer)llList2String(lList, x*iSTRIDE+2);
+				integer iValue = (integer)llList2String(lList, x*iSTRIDE+3);
+				if(iTotalWeight+iWeight<iMAX_WEIGHT) {
+					iTotalWeight += iWeight;
+					iTotalValue += iValue;
+					lKnapsack += [sItem, iWeight, iValue, fValueWeight];
+				}
+				x++;
+			}
+			for(x=0 ; x*iSTRIDE<llGetListLength(lKnapsack) ; x++) {
+				llOwnerSay((string)x+": "+llList2String(lList, x*iSTRIDE+1)+", "+llList2String(lList, x*iSTRIDE+2)+", "+llList2String(lList, x*iSTRIDE+3));
+
+			}
+			llOwnerSay("iTotalWeight="+(string)iTotalWeight);
+			llOwnerSay("iTotalValue="+(string)iTotalValue);
+		} else {
+			//llOwnerSay((string)iNotecardLine+": "+sData);
+			if(llStringTrim(sData, STRING_TRIM)!="") {
+				list lParsed = llParseString2List(sData, [","], []);
+				string sItem = llStringTrim(llList2String(lParsed, 0), STRING_TRIM);
+				integer iWeight = (integer)llStringTrim(llList2String(lParsed, 1), STRING_TRIM);
+				integer iValue = (integer)llStringTrim(llList2String(lParsed, 2), STRING_TRIM);
+				float fValueWeight = (1.0*iValue)/iWeight;
+				lList += [fValueWeight, sItem, iWeight, iValue];
+			}
+			llGetNotecardLine(sNOTECARD, ++iNotecardLine);
+		}
+	}
+}

Task/Knapsack-problem-0-1/LSL/knapsack-problem-0-1-2.lsl

@@ -0,0 +1,85 @@
+items = {
+    {"map", 9, 150},
+    {"compass", 13, 35},
+    {"water", 153, 200},
+    {"sandwich", 50, 160},
+    {"glucose", 15, 60},
+    {"tin", 68, 45},
+    {"banana", 27, 60},
+    {"apple", 39,  40},
+    {"cheese", 23, 30},
+    {"beer", 52, 10},
+    {"suntan cream", 11, 70},
+    {"camera", 32, 30},
+    {"t-shirt", 24, 15},
+    {"trousers", 48, 10},
+    {"umbrella", 73, 40},
+    {"waterproof trousers", 42, 70},
+    {"waterproof overclothes", 43, 75},
+    {"note-case", 22, 80},
+    {"sunglasses", 7, 20},
+    {"towel", 18, 12},
+    {"socks", 4, 50},
+    {"book", 30, 10},
+}
+
+local unpack = table.unpack
+
+function m(i, w)
+    if i<1 or w==0 then
+        return 0, {}
+    else
+        local _, wi, vi = unpack(items[i])
+        if wi > w then
+            return mm(i - 1, w)
+        else
+            local vn, ln = mm(i - 1, w)
+            local vy, ly = mm(i - 1, w - wi)
+            if vy + vi > vn then
+                return vy + vi, { i, ly }
+            else
+                return vn, ln
+            end
+        end
+    end
+end
+
+local memo, mm_calls = {}, 0
+function mm(i, w) -- memoization function for m
+    mm_calls = mm_calls + 1
+    local key = 10000*i + w
+    local result = memo[key]
+    if not result then
+        result = { m(i, w) }
+        memo[key] = result
+    end
+    return unpack(result)
+end
+
+local total_value, index_list = m(#items, 400)
+
+function list_items(head) -- makes linked list iterator function
+    return function()
+        local item, rest = unpack(head)
+        head = rest
+        return item
+    end
+end
+
+local names = {}
+local total_weight = 0
+for i in list_items(index_list) do
+    local name, weight = unpack(items[i])
+    table.insert(names, 1, name)
+    total_weight = total_weight + weight
+end
+
+local function printf(fmt, ...) print(string.format(fmt, ...)) end
+printf("items to pack: %s", table.concat(names, ", "))
+printf("total value: %d", total_value)
+printf("total weight: %d", total_weight)
+
+-- out of curiosity
+local count = 0
+for k,v in pairs(memo) do count = count + 1 end
+printf("\n(memo count: %d; mm call count: %d)", count, mm_calls)