Task: Knapsack problem_Bounded

C: #include <stdio.h>
#include <stdlib.h>

typedef struct {
    char *name;
    int weight;
    int value;
    int count;
} item_t;

item_t items[] = {
    {"map",                      9,   150,   1},
    {"compass",                 13,    35,   1},
    {"water",                  153,   200,   2},
    {"sandwich",                50,    60,   2},
    {"glucose",                 15,    60,   2},
    {"tin",                     68,    45,   3},
    {"banana",                  27,    60,   3},
    {"apple",                   39,    40,   3},
    {"cheese",                  23,    30,   1},
    {"beer",                    52,    10,   3},
    {"suntan cream",            11,    70,   1},
    {"camera",                  32,    30,   1},
    {"T-shirt",                 24,    15,   2},
    {"trousers",                48,    10,   2},
    {"umbrella",                73,    40,   1},
    {"waterproof trousers",     42,    70,   1},
    {"waterproof overclothes",  43,    75,   1},
    {"note-case",               22,    80,   1},
    {"sunglasses",               7,    20,   1},
    {"towel",                   18,    12,   2},
    {"socks",                    4,    50,   1},
    {"book",                    30,    10,   2},
};

int n = sizeof (items) / sizeof (item_t);

int *knapsack (int w) {
    int i, j, k, v, *mm, **m, *s;
    mm = calloc((n + 1) * (w + 1), sizeof (int));
    m = malloc((n + 1) * sizeof (int *));
    m[0] = mm;
    for (i = 1; i <= n; i++) {
        m[i] = &mm[i * (w + 1)];
        for (j = 0; j <= w; j++) {
            m[i][j] = m[i - 1][j];
            for (k = 1; k <= items[i - 1].count; k++) {
                if (k * items[i - 1].weight > j) {
                    break;
                }
                v = m[i - 1][j - k * items[i - 1].weight] + k * items[i - 1].value;
                if (v > m[i][j]) {
                    m[i][j] = v;
                }
            }
        }
    }
    s = calloc(n, sizeof (int));
    for (i = n, j = w; i > 0; i--) {
        int v = m[i][j];
        for (k = 0; v != m[i - 1][j] + k * items[i - 1].value; k++) {
            s[i - 1]++;
            j -= items[i - 1].weight;
        }
    }
    free(mm);
    free(m);
    return s;
}

int main () {
    int i, tc = 0, tw = 0, tv = 0, *s;
    s = knapsack(400);
    for (i = 0; i < n; i++) {
        if (s[i]) {
            printf("%-22s %5d %5d %5d\n", items[i].name, s[i], s[i] * items[i].weight, s[i] * items[i].value);
            tc += s[i];
            tw += s[i] * items[i].weight;
            tv += s[i] * items[i].value;
        }
    }
    printf("%-22s %5d %5d %5d\n", "count, weight, value:", tc, tw, tv);
    return 0;
}







Python: 

import strformat
import tables


type Item = tuple[name: string; weight, value, pieces: int]


const Items: seq[Item] = @[("map", 9, 150, 1),
                           ("compass", 13, 35, 1),
                           ("water", 153, 200, 2),
                           ("sandwich", 50, 60, 2),
                           ("glucose", 15, 60, 2),
                           ("tin", 68, 45, 3),
                           ("banana", 27, 60, 3),
                           ("apple", 39, 40, 3),
                           ("cheese", 23, 30, 1),
                           ("beer", 52, 10, 3),
                           ("suntan cream", 11, 70, 1),
                           ("camera", 32, 30, 1),
                           ("T-shirt", 24, 15, 2),
                           ("trousers", 48, 10, 2),
                           ("umbrella", 73, 40, 1),
                           ("waterproof trousers", 42, 70, 1),
                           ("waterproof overclothes", 43, 75, 1),
                           ("note-case", 22, 80, 1),
                           ("sunglasses", 7, 20, 1),
                           ("towel", 18, 12, 2),
                           ("socks", 4, 50, 1),
                           ("book", 30, 10, 2)
                          ]

type

  
  Number = range[0..Items.high]

  
  ExpandedItem = tuple[num: Number; weight, value: int]




proc expandedItems(items: seq[Item]): seq[ExpandedItem] =
  
  for idx, item in Items:
    for _ in 1..item.pieces:
      result.add((idx.Number, item.weight, item.value))

const ItemList = expandedItems(Items)

type

  
  ExpandedIndex = 0..ItemList.high

  
  Choice = tuple[indexes: set[ExpandedIndex]; weight, value: int]


var cache: Table[tuple[index, weight: int], Choice]




proc select(idx, weightLimit: int): Choice =
  

  if idx < 0 or weightLimit == 0:
    return

  if (idx, weightLimit) in cache:
    return cache[(idx, weightLimit)]

  let weight = ItemList[idx].weight
  if weight > weightLimit:
    return select(idx - 1, weightLimit)

  
  result = select(idx - 1, weightLimit)

  
  var result1 = select(idx - 1, weightLimit - weight)
  inc result1.value, ItemList[idx].value

  
  if result1.value > result.value:
    result = (result1.indexes + {idx.ExpandedIndex}, result1.weight + weight, result1.value)

  cache[(idx, weightLimit)] = result



let (indexes, weight, value) = select(ItemList.high, 400)


var pieces = newSeq[int](Items.len)
for idx in indexes:
  inc pieces[ItemList[idx].num]

echo "List of items:"
for num in 0..Items.high:
  if pieces[num] > 0:
    echo fmt"– {pieces[num]} of {Items[num].pieces} {Items[num].name}"
echo ""
echo "Total weight: ", weight
echo "Total value: ", value