36 lines
633 B
C++
36 lines
633 B
C++
#include <iostream>
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#include <vector>
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#include <unordered_map>
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using namespace std;
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int main(){
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int n, m;
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cin >> n >> m;
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vector<int> arr(n);
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vector<int> dp(m + 1, 0);
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unordered_map<int, int> mp;
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for(int i = 0; i < n; i++){
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cin >> arr[i];
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mp[i]++;
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}
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dp[0] = 1;
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//dp[i] += dp[i - arr[j]]
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/* 0/1背包必须得j在外层，不依赖前面的d[i]
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for(int i = 1; i <= m; i++){
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for(int j = 0; j < n; j++){
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if(i - arr[j] >= 0) {
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dp[i] += dp[i - arr[j]];
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}
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}
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}*/
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//不重复利用元素
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for(int j = 0; j < n; j++){
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for(int i = m; i >= arr[j]; i--){
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dp[i] += dp[i - arr[j]];
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}
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}
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cout << dp[m] << endl;
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return 0;
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}
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