PROGRAM Time_MST
      USE Precision
      USE Error_Handling
      USE System_Monitors
      USE Random_Numbers
      USE Sorting_Ranking
      USE Initialization_Termination
      USE Network_Data_Structures
      USE Lattice_Geometry
      USE Network_Geometry
      USE Network_Graphics
      USE Lattice_Network_Optimization
      USE Graph_Algorithms
      USE Network_Spanning_Trees
      USE Power_Cost_Parameters
      IMPLICIT NONE
      
      REAL(KIND=r_wp),DIMENSION(:),ALLOCATABLE::weights_changes,arcs_weights
      INTEGER(KIND=i_wp)::arc,node,head,tail,n_pivoted
      REAL(KIND=r_wp)::disorder,total_weight
      
      CALL StartProgram
      CALL InitializeLatticeNetworkProblem
      CALL CreateLatticeNetworkProblem
      ALLOCATE(arcs_weights(-n_special_arcs:n_arcs),weights_changes(-n_special_arcs:n_arcs))
      debug_graph_algs=.TRUE.
      
      OPEN(FILE="MST.dat",UNIT=101,STATUS="UNKNOWN",ACTION="WRITE",POSITION="APPEND")
      OPEN(FILE="MST.total.dat",UNIT=201,STATUS="UNKNOWN",ACTION="WRITE",POSITION="APPEND")
      WRITE(UNIT=101,FMT="(2I5,I15)",ADVANCE="NO")lengths,PRODUCT(lengths)
      WRITE(UNIT=201,FMT="(I15)",ADVANCE="NO")PRODUCT(lengths)
      
      arcs_weights=arcs_cost_parameters(1,:)
      
      CALL ResetTimer(1)
      CALL StartTimer(1)
      CALL CreateSpanningTree(tree_type=min_cost_tree,arcs_weights=arcs_weights,&
      weights_distribution=costs_distribution,&
      tree_timer=2,thread_timer=3)
      CALL StopTimer(1)
      WRITE(*,*)"Making the MST tree from scratch took:",ReadTimer(1)
      WRITE(*,*)"____________________     Tree bulding:",ReadTimer(2)
      WRITE(*,*)"____________________  Thread building:",ReadTimer(3)
      WRITE(UNIT=101,FMT="(3E10.3)",ADVANCE="NO")ReadTimer(2),ReadTimer(3),ReadTimer(1)
      
      WRITE(UNIT=201,FMT="(E10.3)",ADVANCE="NO")ReadTimer(1)
      
      WRITE(*,*)"Enter the disorder:"
      READ(*,*)disorder
      WRITE(UNIT=101,FMT="(F6.2)",ADVANCE="NO")disorder
      
      CALL RandomUniform(weights_changes,range=(/1.0_r_wp-disorder,1.0_r_wp+disorder/))
      arcs_weights=weights_changes*arcs_weights
      
      CALL ResetTimer(10)
      CALL StartTimer(10)
      CALL UpdateSpanningTree(tree_type=min_cost_tree,arcs_weights=arcs_weights,&
      n_pivots=n_pivoted,tree_timer=15,thread_timer=16)
      CALL StopTimer(10)
      
      WRITE(*,*)"Rebuilding the MST tree took         :",ReadTimer(10)
      WRITE(*,*)"____________________  Tree rebuilding:",ReadTimer(15)
      WRITE(*,*)"____________________  Thread building:",ReadTimer(16)
      WRITE(UNIT=101,FMT="(3E10.3,I10)",ADVANCE="NO")&
      ReadTimer(15),ReadTimer(16),ReadTimer(10),n_pivoted
      WRITE(UNIT=201,FMT="(1E10.3)",ADVANCE="NO")ReadTimer(10)
      
      WRITE(101,*)
      CLOSE(UNIT=101)
      WRITE(201,*)
      CLOSE(UNIT=201)
      
      CALL DestroyLatticeNetworkProblem
      CALL EndProgram
      
      END PROGRAM Time_MST