我正在寫一個函數種類模仿unordered_tuple
從sage combinatorial functions python中可用。生成一個有序的選擇重複的指定長度的條目
不同之處在於,我使用的輸入集總是[10,9,8,7,6],並且只有輸入項數量變化(不大於10)。
所以,期望的輸出爲輸入= 3和用於輸入= 4,
unordered_tuples([10,9,8,7,6], 3)
[[6, 6, 6],
[6, 6, 7],
[6, 6, 8],
[6, 6, 9],
[6, 6, 10],
[6, 7, 7],
[6, 7, 8],
[6, 7, 9],
[6, 7, 10],
[6, 8, 8],
[6, 8, 9],
[6, 8, 10],
[6, 9, 9],
[6, 9, 10],
[6, 10, 10],
[7, 7, 7],
[7, 7, 8],
[7, 7, 9],
[7, 7, 10],
[7, 8, 8],
[7, 8, 9],
[7, 8, 10],
[7, 9, 9],
[7, 9, 10],
[7, 10, 10],
[8, 8, 8],
[8, 8, 9],
[8, 8, 10],
[8, 9, 9],
[8, 9, 10],
[8, 10, 10],
[9, 9, 9],
[9, 9, 10],
[9, 10, 10],
[10, 10, 10]]
unordered_tuples([10,9,8,7,6], 4)
[[6, 6, 6, 6],
[6, 6, 6, 7],
[6, 6, 6, 8],
[6, 6, 6, 9],
[6, 6, 6, 10],
[6, 6, 7, 7],
[6, 6, 7, 8],
[6, 6, 7, 9],
[6, 6, 7, 10],
[6, 6, 8, 8],
[6, 6, 8, 9],
[6, 6, 8, 10],
[6, 6, 9, 9],
[6, 6, 9, 10],
[6, 6, 10, 10],
[6, 7, 7, 7],
[6, 7, 7, 8],
[6, 7, 7, 9],
[6, 7, 7, 10],
[6, 7, 8, 8],
[6, 7, 8, 9],
[6, 7, 8, 10],
[6, 7, 9, 9],
[6, 7, 9, 10],
[6, 7, 10, 10],
[6, 8, 8, 8],
[6, 8, 8, 9],
[6, 8, 8, 10],
[6, 8, 9, 9],
[6, 8, 9, 10],
[6, 8, 10, 10],
[6, 9, 9, 9],
[6, 9, 9, 10],
[6, 9, 10, 10],
[6, 10, 10, 10],
[7, 7, 7, 7],
[7, 7, 7, 8],
[7, 7, 7, 9],
[7, 7, 7, 10],
[7, 7, 8, 8],
[7, 7, 8, 9],
[7, 7, 8, 10],
[7, 7, 9, 9],
[7, 7, 9, 10],
[7, 7, 10, 10],
[7, 8, 8, 8],
[7, 8, 8, 9],
[7, 8, 8, 10],
[7, 8, 9, 9],
[7, 8, 9, 10],
[7, 8, 10, 10],
[7, 9, 9, 9],
[7, 9, 9, 10],
[7, 9, 10, 10],
[7, 10, 10, 10],
[8, 8, 8, 8],
[8, 8, 8, 9],
[8, 8, 8, 10],
[8, 8, 9, 9],
[8, 8, 9, 10],
[8, 8, 10, 10],
[8, 9, 9, 9],
[8, 9, 9, 10],
[8, 9, 10, 10],
[8, 10, 10, 10],
[9, 9, 9, 9],
[9, 9, 9, 10],
[9, 9, 10, 10],
[9, 10, 10, 10],
[10, 10, 10, 10]]
和C++函數我寫如下。
我其實不是一個有經驗的程序員,我只是試圖想出正確的解決方案,但它工作正常,但它提供了許多重複的解決方案。
老實說,我寫了這個函數,但我甚至不知道自己寫了什麼。
我可以使用set
,但它會是非常低效的,我想知道這個問題的正確解決方案。
任何人都可以修復它,以便它提供上面的輸出?
#include<iostream>
#include<string>
#include<cstdlib>
#include<vector>
using namespace std;
vector<vector<int> > ut(int);
int main(int argc, char** argv) {
int entry = atoi(argv[1]);
ut(entry);
return 1;
}
vector<vector<int> > ut(int entry) {
vector<vector<int> > ret;
int upper = 10;
vector<int> v(entry, upper);
ret.push_back(v);
typedef vector<int>::iterator iter_t;
iter_t it = v.begin();
int count=0;
int c = 0;
while(v.back() != 6) {
v = ret[count+c];
while(it != v.end()) {
--(*it);
++it;
ret.push_back(v);
++c;
}
it = v.begin();
c=0;
++count;
}
for(int i=0; i<ret.size(); ++i) {
vector<int> tuple = ret[i];
for(int j=0; j<tuple.size(); ++j) {
cout << tuple[j] << ' ';
}
cout<<endl;
}
cout << endl;
return ret;
}
獲得正確的功能第一,擔心以後的效率。 –
如果我只是將向量的返回類型更改爲set,則該函數可以正常工作。我不確定我的算法是否「好」或不好 – user2418202
此代碼似乎產生未定義的行爲。你想讓我們告訴你它錯在哪裏以及如何解決它,或者給你一個有效的算法? – Beta