diff options
Diffstat (limited to 'content/graph/bitonicTSP.cpp')
| -rw-r--r-- | content/graph/bitonicTSP.cpp | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/content/graph/bitonicTSP.cpp b/content/graph/bitonicTSP.cpp new file mode 100644 index 0000000..6470232 --- /dev/null +++ b/content/graph/bitonicTSP.cpp @@ -0,0 +1,31 @@ +vector<vector<double>> dist; // Initialisiere mit Entfernungen zwischen Punkten. + +auto bitonicTSP() { + vector<double> dp(sz(dist), HUGE_VAL); + vector<int> pre(sz(dist)); // nur für Tour + dp[0] = 0; dp[1] = 2 * dist[0][1]; pre[1] = 0; + for (unsigned int i = 2; i < sz(dist); i++) { + double link = 0; + for (int j = i - 2; j >= 0; j--) { + link += dist[j + 1][j + 2]; + double opt = link + dist[j][i] + dp[j + 1] - dist[j][j + 1]; + if (opt < dp[i]) { + dp[i] = opt; + pre[i] = j; + }}} + // return dp.back(); // Länger der Tour + + int j, n = sz(dist) - 1; + vector<int> ut, lt = {n, n - 1}; + do { + j = pre[n]; + (lt.back() == n ? lt : ut).push_back(j); + for (int i = n - 1; i > j + 1; i--) { + (lt.back() == i ? lt : ut).push_back(i - 1); + } + } while(n = j + 1, j > 0); + (lt.back() == 1 ? lt : ut).push_back(0); + reverse(all(lt)); + lt.insert(lt.end(), all(ut)); + return lt;// Enthält Knoten 0 zweimal. An erster und letzter Position. +} |
