[eb793a] | 1 | #include <Singular/libsingular.h> |
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| 2 | |
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| 3 | #include <vector> |
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| 4 | |
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| 5 | void subset(std::vector<int> &arr, int size, int left, int index, std::vector<int> &l, std::vector<std::vector<int> > &L) |
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| 6 | { |
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| 7 | if(left==0) |
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| 8 | { |
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| 9 | L.push_back(l); |
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| 10 | return; |
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| 11 | } |
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| 12 | |
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| 13 | for(int i=index; i<size;i++) |
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| 14 | { |
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| 15 | l.push_back(arr[i]); |
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| 16 | subset(arr,size,left-1,i+1,l,L); |
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| 17 | l.pop_back(); |
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| 18 | } |
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| 19 | } |
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| 20 | |
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| 21 | BOOLEAN subsets(leftv res, leftv args) |
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| 22 | { |
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| 23 | leftv u = args; |
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| 24 | if ((u!=NULL) && (u->Typ()==INT_CMD)) |
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| 25 | { |
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| 26 | leftv v = u->next; |
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| 27 | if ((v!=NULL) && (v->Typ()==INT_CMD) && (v->next==NULL)) |
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| 28 | { |
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| 29 | int n = (int)(long) u->Data(); |
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| 30 | int k = (int)(long) v->Data(); |
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| 31 | std::vector<int> array(n); |
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| 32 | for (int i=0; i<n; i++) |
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| 33 | array[i]=i+1; |
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| 34 | std::vector<int> ltemp; |
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| 35 | std::vector<std::vector<int> > lt; |
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| 36 | subset(array,n,k,0,ltemp,lt); |
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| 37 | |
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| 38 | lists Lt = (lists) omAllocBin(slists_bin); |
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| 39 | Lt->Init(lt.size()); |
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| 40 | for (int i=0; i<lt.size(); i++) |
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| 41 | { |
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| 42 | std::vector<int> lti = lt[i]; |
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| 43 | lists Lti = (lists) omAllocBin(slists_bin); |
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| 44 | Lti->Init(k); |
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| 45 | for(int j=0; j<lti.size(); j++) |
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| 46 | { |
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| 47 | Lti->m[j].rtyp = INT_CMD; |
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| 48 | Lti->m[j].data = (void*)(long)lti[j]; |
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| 49 | } |
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| 50 | Lt->m[i].rtyp = LIST_CMD; |
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| 51 | Lt->m[i].data = (void*) Lti; |
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| 52 | } |
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| 53 | |
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| 54 | res->rtyp = LIST_CMD; |
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| 55 | res->data = (void*) Lt; |
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| 56 | return FALSE; |
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| 57 | } |
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| 58 | } |
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| 59 | WerrorS("subsets: unexpected parameter"); |
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| 60 | return TRUE; |
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| 61 | } |
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| 62 | |
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| 63 | //------------------------------------------------------------------------ |
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| 64 | // initialisation of the module |
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| 65 | extern "C" int SI_MOD_INIT(customstd)(SModulFunctions* p) |
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| 66 | { |
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| 67 | p->iiAddCproc("general.lib","subsets",FALSE,subsets); |
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| 68 | return (MAX_TOK); |
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| 69 | } |
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