HDU 1258 Sum It Up(哈希表判重)

判重哈希表解决：

[cpp]
#include <iostream>
using namespace std;
const int nMax = 15;
const int INF = 10007;
int t, n;
int A[nMax];
int flag;
int hash[INF][15];
int head[INF];
//int head[], next[];
//int ans[nMax];
//int len;

bool isSame(int *a, int *b, int len)
{
    if(a[0] != len)
        return 0;
    int i;
    for(i = 0; i < len; ++ i)
        if(a[1 + i] != b[i])
            return 0;
    return 1;
}

int insert(int *ans, int len)
{
    int k = 0;
    int i;
    for(i = 0; i < len; ++ i)
        k = (k * 10 + ans[i]) % INF;
    while(head[k] != 0 && !isSame(hash[k], ans, len))
    {
        k ++;
        k %= INF;
    }
    if(head[k] == 0)
    {
        head[k] = 1;
        hash[k][0] = len;
        memcpy(hash[k] + 1, ans, len * sizeof(int));//memcpy最后的长度最后能够自己定义出来
        return 1;
    }
    return 0;
}

void dfs(int pos, int m, int *ans, int len)
{
    if(pos >= n)
        return;
    if(A[pos] <= m)
    {
        ans[len] = A[pos];
        if(A[pos] == m)
        {
            flag = 1;
            if(insert(ans, len + 1))//这里的len需要加1来保证程序的正常判断
            {
                int i;
                for(i = 0; i <= len; ++ i)
                {
                    if(i)
                        printf("+");
                    printf("%d", ans[i]);
                }
                printf("\n");
            }
        }
        else
            dfs(pos + 1, m - A[pos], ans, len + 1);
    }
    /*
    int p = pos + 1;
    while(A[p] == A[pos])
        p ++;
    */
    dfs(pos + 1, m, ans, len);
}

int main()
{
    //freopen("e://data.in", "r", stdin);
    while(scanf("%d%d", &t, &n) != EOF)
    {
        if(n == 0)
            break;
        int i;
        for(i = 0; i < n; ++ i)
            scanf("%d", &A[i]);
        int ans[nMax];
        flag = 0;
        printf("Sums of %d:\n", t);
        dfs(0, t, ans, 0);
        if(flag == 0)
            printf("NONE\n");
    }
    return 0;
}

补充：软件开发 , C++ ,