diff options
Diffstat (limited to 'src/lesson40_algo12.cpp')
| -rw-r--r-- | src/lesson40_algo12.cpp | 28 |
1 files changed, 11 insertions, 17 deletions
diff --git a/src/lesson40_algo12.cpp b/src/lesson40_algo12.cpp index 8107551..2e8580c 100644 --- a/src/lesson40_algo12.cpp +++ b/src/lesson40_algo12.cpp @@ -353,35 +353,29 @@ namespace hoare3 { const size_t hi = e-1; size_t l = b + 1, g = hi - 1; // pivot points { - const V& P = std::min(A[b], A[hi]); // Pivot 1, ref only - const V& Q = std::max(A[b], A[hi]); // Pivot 2, ref only + if( A[b] > A[hi] ) { + std::swap(A[b], A[hi]); + } + const V& p = A[b]; // Pivot 1, ref only + const V& q = A[hi]; // Pivot 2, ref only size_t k = l; while (k <= g) { - if (A[k] < P) { + if (A[k] < p) { std::swap(A[k], A[l]); ++l; - } else if( A[k] >= Q ) { - while( A[g] > Q && k < g ) { + } else if( A[k] >= q ) { + while( A[g] > q && k < g ) { --g; } std::swap(A[k], A[g]); --g; - if( A[k] < P ) { + if( A[k] < p ) { std::swap(A[k], A[l]); ++l; } } ++k; } --l; ++g; - { - // 2x 3-way swap using std::move - V t = std::move(P); - V u = std::move(Q); - // 1: A[b] = A[l]; A[l] = P; - A[b] = std::move(A[l]); - A[l] = std::move(t); - // 2: A[hi] = A[g]; A[g] = Q; - A[hi] = std::move(A[g]); - A[g] = std::move(u); - } + std::swap(A[b], A[l]); + std::swap(A[hi], A[g]); } // Recursion |