Task: Subset sum problem
C: #include <stdio.h>
#include <stdlib.h>

typedef struct {
    char *word;
    int weight;
} item_t;

item_t items[] = {
    {"alliance",     -624},
    {"archbishop",   -915},
    {"balm",          397},
    {"bonnet",        452},
    {"brute",         870},
    {"centipede",    -658},
    {"cobol",         362},
    {"covariate",     590},
    {"departure",     952},
    {"deploy",         44},
    {"diophantine",   645},
    {"efferent",       54},
    {"elysee",       -326},
    {"eradicate",     376},
    {"escritoire",    856},
    {"exorcism",     -983},
    {"fiat",          170},
    {"filmy",        -874},
    {"flatworm",      503},
    {"gestapo",       915},
    {"infra",        -847},
    {"isis",         -982},
    {"lindholm",      999},
    {"markham",       475},
    {"mincemeat",    -880},
    {"moresby",       756},
    {"mycenae",       183},
    {"plugging",     -266},
    {"smokescreen",   423},
    {"speakeasy",    -745},
    {"vein",          813},
};

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

void subsum (int i, int weight) {
    int j;
    if (i && !weight) {
        for (j = 0; j < i; j++) {
            item_t item = items[set[j]];
            printf("%s%s", j ? " " : "", items[set[j]].word);
        }
        printf("\n");
    }
    for (j = i ? set[i - 1] + 1: 0; j < n; j++) {
        set[i] = j;
        subsum(i + 1, weight + items[j].weight);
    }
}

int main () {
    set = malloc(n * sizeof (int));
    subsum(0, 0);
    return 0;
}

C#: using System;
using System.Collections.Generic;

namespace SubsetSum {
    class Item {
        public Item(string word, int weight) {
            Word = word;
            Weight = weight;
        }

        public string Word { get; set; }
        public int Weight { get; set; }

        public override string ToString() {
            return string.Format("({0}, {1})", Word, Weight);
        }
    }

    class Program {
        private static readonly List<Item> items = new List<Item>() {
            new Item("alliance", -624),
            new Item("archbishop", -915),
            new Item("balm", 397),
            new Item("bonnet", 452),
            new Item("brute", 870),
            new Item("centipede", -658),
            new Item("cobol", 362),
            new Item("covariate", 590),
            new Item("departure", 952),
            new Item("deploy", 44),
            new Item("diophantine", 645),
            new Item("efferent", 54),
            new Item("elysee", -326),
            new Item("eradicate", 376),
            new Item("escritoire", 856),
            new Item("exorcism", -983),
            new Item("fiat", 170),
            new Item("filmy", -874),
            new Item("flatworm", 503),
            new Item("gestapo", 915),
            new Item("infra", -847),
            new Item("isis", -982),
            new Item("lindholm", 999),
            new Item("markham", 475),
            new Item("mincemeat", -880),
            new Item("moresby", 756),
            new Item("mycenae", 183),
            new Item("plugging", -266),
            new Item("smokescreen", 423),
            new Item("speakeasy", -745),
            new Item("vein", 813),
        };

        private static readonly int n = items.Count;
        private static readonly int LIMIT = 5;

        private static int[] indices = new int[n];
        private static int count = 0;

        private static void ZeroSum(int i, int w) {
            if (i != 0 && w == 0) {
                for (int j = 0; j < i; j++) {
                    Console.Write("{0} ", items[indices[j]]);
                }
                Console.WriteLine("\n");
                if (count < LIMIT) count++;
                else return;
            }
            int k = (i != 0) ? indices[i - 1] + 1 : 0;
            for (int j = k; j < n; j++) {
                indices[i] = j;
                ZeroSum(i + 1, w + items[j].Weight);
                if (count == LIMIT) return;
            }
        }

        static void Main(string[] args) {
            Console.WriteLine("The weights of the following {0} subsets add up to zero:\n", LIMIT);
            ZeroSum(0, 0);
        }
    }
}