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# kuoe0/GT-TSP-DP.cpp

Last active June 26, 2018 15:13
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[Algorithm] Traveling Salesman's Problem - DP solution - http://kuoe0.ch/1878/algorithm-traveling-salesman-s-problem-dp-solution
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 /*============================================================================= # FileName: GT-TSP-DP.cpp # Desc: Traveling Salesman Problem - DP solution # Author: KuoE0 # Email: kuoe0.tw@gmail.com # HomePage: http://kuoe0.ch/ # Version: 0.0.1 # LastChange: 2012-10-11 20:59:01 # History: =============================================================================*/ #include #include #include #include using namespace std; int n, src; vector< vector< int > > graph, dp; // initial status void init() { for ( int i = 0; i < n; ++i ) dp[ 1 << i ][ i ] = graph[ src ][ i ]; } // TSP recursive int TSP( int status, int x ) { if ( dp[ status ][ x ] != -1 ) return dp[ status ][ x ]; int mask = 1 << x; dp[ status ][ x ] = 1e9; for ( int i = 0; i < n; ++i ) if ( i != x && ( status & ( 1 << i ) ) ) dp[ status ][ x ] = min( dp[ status ][ x ], TSP( status - mask, i ) + graph[ i ][ x ] ); return dp[ status ][ x ]; } int main() { scanf( "%d %d", &n, &src ); graph = vector< vector< int > >( n, vector< int >( n ) ); dp = vector< vector< int > >( 1 << n, vector< int >( n, -1 ) ); for ( int i = 0; i < n; ++i ) for ( int j = 0; j < n; ++j ) { int x; scanf( "%d", &x ); graph[ i ][ j ] = x; } init(); printf( "%d\n", TSP( ( 1 << n ) - 1, src ) ); return 0; }

### RajeshUppala commented Jan 29, 2015

Your TSP implementation is awesome. Can you make changes to your code and print the path