题目链接:56. 携带矿石资源(第八期模拟笔试) (kamacoder.com)
#include<iostream>
#include<vector>
using namespace std;
int main() {int bagWeight,n;cin >> bagWeight >> n;vector<int> weight(n, 0);vector<int> value(n, 0);vector<int> nums(n, 0);for (int i = 0; i < n; i++) cin >> weight[i];for (int i = 0; i < n; i++) cin >> value[i];for (int i = 0; i < n; i++) cin >> nums[i];vector<int> dp(bagWeight + 1, 0);for(int i = 0; i < n; i++) { // 遍历物品for(int j = bagWeight; j >= weight[i]; j--) { // 遍历背包容量// 以上为01背包,然后加一个遍历个数for (int k = 1; k <= nums[i] && (j - k * weight[i]) >= 0; k++) { // 遍历个数dp[j] = max(dp[j], dp[j - k * weight[i]] + k * value[i]);}}}cout << dp[bagWeight] << endl;
}
多重背包,即每个物品都有不只一个,思路和01背包一样。我们只需要把物品展开就行。代码随想录 (programmercarl.com)
题目链接:139. 单词拆分 - 力扣(LeetCode)
class Solution {
public:bool wordBreak(string s, vector<string>& wordDict) {unordered_set<string> wordSet(wordDict.begin(), wordDict.end());vector<bool> dp(s.size() + 1, false);dp[0] = true;for (int i = 1; i <= s.size(); i++) { // 遍历背包for (int j = 0; j < i; j++) { // 遍历物品string word = s.substr(j, i - j); //substr(起始位置,截取的个数)if (wordSet.find(word) != wordSet.end() && dp[j]) {dp[i] = true;}}}return dp[s.size()];}
};
好晕