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1、Tyvj 1214 硬幣問題

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <algorithm>
#include <queue>
#include <vector>
#include <stack>
#include <map>
#include <set>
#include <cmath>
#include <cctype>
#include <ctime>
#include <cassert>

using namespace std;

#define REP(i, n) for (int i = 0; i < (n); ++i)
#define eps 1e-9

typedef long long ll;
typedef pair<int, int> Pair;

const int INF = 0x7fffffff;
const int maxn = 110;
int a[maxn], Max[10010], Min[10010];
int n, s;

int dfs_Max(int u);
int dfs_Min(int u);

int main() {
#ifdef __AiR_H
    freopen("in.txt", "r", stdin);
#endif // __AiR_H
    scanf("%d %d", &n, &s);
    REP(i, n) { scanf("%d", &a[i]); }
    sort(a, a + n);
    memset(Max, -1, sizeof(Max)); Max[0] = 0; Min[0] = 0;
    for (int i = 1; i <= s; ++i) { Min[i] = INF; }
    dfs_Max(s); dfs_Min(s);
    printf("%d\n", Min[s]);
    printf("%d\n", Max[s]);
#ifdef __AiR_H
    printf("Time used = %.2fs\n", (double)clock() / CLOCKS_PER_SEC);
#endif // __AiR_H
    return 0;
}

int dfs_Max(int u) {
    if (Max[u] < -1) { return -1; }
    if (Max[u] >= 0) { return Max[u]; }
    int max_t = -INF, t = 0;
    REP(i, n) {
        if (u < a[i]) { break; }
        t = dfs_Max(u - a[i]);
        if (t != -1) { max_t = max(max_t, 1 + t); }
    }
    return Max[u] = max_t;
}

int dfs_Min(int u) {
    if (Min[u] < INF) { return Min[u]; }
    int min_t = INF - 1, t = 0;
    REP(i, n) {
        if (u < a[i]) { break; }
        t = dfs_Min(u - a[i]);
        if (t < INF - 1) { min_t = min(min_t, 1 + t); }
    }
    return Min[u] = min_t;
}

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <algorithm>
#include <queue>
#include <vector>
#include <stack>
#include <map>
#include <set>
#include <cmath>
#include <cctype>
#include <ctime>
#include <cassert>

using namespace std;

#define REP(i, n) for (int i = 0; i < (n); ++i)
#define eps 1e-9

typedef long long ll;
typedef pair<int, int> Pair;

const int INF = 0x3f3f3f3f;
const int maxn = 110;
int a[maxn], Max[10010], Min[10010];
int n, s;

int main() {
#ifdef __AiR_H
    freopen("in.txt", "r", stdin);
#endif // __AiR_H
    scanf("%d %d", &n, &s);
    REP(i, n) { scanf("%d", &a[i]); }
    sort(a, a + n);
    Max[0] = 0; Min[0] = 0;
    for (int i = 1; i <= s; ++i) { Min[i] = INF; Max[i] = -INF; }
    for (int i = 1; i <= s; ++i) {
        REP(j, n) {
            if (i < a[j]) { break; }
            Min[i] = min(Min[i], Min[i - a[j]] + 1);
            Max[i] = max(Max[i], Max[i - a[j]] + 1);
        }
    }
    printf("%d\n", Min[s]);
    printf("%d\n", Max[s]);
#ifdef __AiR_H
    printf("Time used = %.2fs\n", (double)clock() / CLOCKS_PER_SEC);
#endif // __AiR_H
    return 0;
}