1068 Find More Coins (30分)

dfs

#include<cstdio>
#include<vector>
#include<algorithm>
#include<unordered_set>
using namespace std;
int n, price;
int coins[10001];
bool visited[102][10002];
vector<int> res;
bool dfs(int remain, int index) {
	if (remain == 0)
		return true;
	if (remain < 0 || index > n || visited[remain][index])
		return false;
	visited[remain][index] = true;
	res.push_back(coins[index]);
	if (dfs(remain - coins[index], index + 1))
		return true;
	res.pop_back();
	return dfs(remain, index + 1);
}
int main() {
	scanf("%d %d", &n, &price);
	for (int i = 0;i < n;i++) {
		scanf("%d", &coins[i]);
	}
	sort(coins, coins + n);
	dfs(price, 0);
	if (res.empty()) {
		printf("No Solution");
		return 0;
	}
	for (int i = 0;i < res.size();i++) {
		if (i != 0)
			printf(" ");
		printf("%d", res[i]);
	}
}

dp

#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
int dp[10010], w[10010];
bool choice[10010][110];
int cmp1(int a, int b){return a > b;}
int main() {
    int n, m;
    scanf("%d%d", &n, &m);
    for(int i = 1; i <= n; i++)
        scanf("%d", &w[i]);
    sort(w + 1, w + n + 1, cmp1);
    for(int i = 1; i <= n; i++) {
        for(int j = m; j >= w[i]; j--) {
            if(dp[j] <= dp[j-w[i]] + w[i]) {
                choice[i][j] = true;
                dp[j] = dp[j-w[i]] + w[i];
            }
        }
    }
    if(dp[m] != m) printf("No Solution");
    else {
        vector<int> arr;
        int v = m, index = n;
        while(v > 0) {
            if(choice[index][v] == true) {
                arr.push_back(w[index]);
                v -= w[index];
            }
            index--;
        }
        for(int i = 0; i < arr.size(); i++) {
            if(i != 0) printf(" ");
            printf("%d", arr[i]);
        }
    }
    return 0;
}