mergesort
C / C++ / MFC
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I'm trying to implement mergesort in C++ but I've grown blind to my code and can't seem to spot the error. It sorts my vector partly, but not entirely. Anyway here's the relevant code:
void merge_sort( std::vector &d, int lb, int ub ) { if( lb < ub ) { int q = ( lb + ub ) / 2; merge_sort( d, lb, q ); merge_sort( d, q + 1, ub ); merge( d, lb, q, ub ); } } void merge( std::vector &d, int lb, int sp, int ub ) { int l1 = sp - lb; int l2 = ub - sp; std::vector vL(d.begin() + lb ,d.begin() + lb + l1); std::vector vR(d.begin() + sp , d.begin() + sp + l2); vL.push_back(INT_MAX); vR.push_back(INT_MAX); int i = 0; int j = 0; for( int k = lb; k < ub; k++ ) { if( vL[i] < vR[j] ) d[k] = vL[i++]; else d[k] = vR[j++]; } }Any help appriciated :)