[Help-glpk] No feasible solution

[Bruno Soares]

Hi,

I have some problems with this code, because in output show this menssege: PROBLEM HAS NO PRIMAL FEASIBLE SOLUTION. I have no ideia why this. Need some help.

param n, integer, > 0;
param Cap, integer, > 0;

set N := 1..n;

param E{i in N, j in N}, >= 0;
param traf{i in N, j in N}, >=0;

var X{i in N, j in N}, integer, >= 0;
var C{s in N, d in N, i in N, j in N}, integer, >= 0;
var OEO{i in N}, integer, >=0;
var OEOm, integer, >=0;

s.t. agrupamento{i in N, j in N}: if (E[i,j]=1) then sum {s in N, d in N} if (s<>d) then C[s,d,i,j] = X[i,j];

s.t. ContFluxo1{s in N, d in N, i in N}: if (s<>d) and (i=s) then (sum{j in N} if (E[i,j]=1) then C[s,d,i,j]) -  (sum{j in N} if (E[i,j]=1) then C[s,d,j,i]) = traf[s,d];

s.t. ContFluxo2{s in N, d in N, i in N}: if (s<>d) and (i=d) then (sum{j in N} if (E[i,j]=1) then C[s,d,i,j]) -  (sum{j in N} if (E[i,j]=1) then C[s,d,j,i]) = - traf[s,d];

s.t. ContFluxo3{s in N, d in N, i in N}: if (s<>d) and (i<>d) and (i<>s) then (sum{j in N} if (E[i,j]=1) then C[s,d,i,j]) -  (sum{j in N} if (E[i,j]=1) then C[s,d,j,i]) = 0;

s.t. const{i in N}: OEOm >= (sum{j in N} if (E[i,j]=1) then X[i,j])/Cap;

minimize obj: OEOm;


data;

param n := 6;

param Cap := 25;

/*matriz de adjacências*/
param E : 1  2  3  4  5  6  :=
      1   0  1  0  0  0  1
      2   1  0  1  0  1  0
      3   0  1  0  1  0  0
      4   0  0  1  0  1  0
      5   0  1  0  1  0  1
      6   1  0  0  0  1  0;

param traf: 1  2  3  4  5  6  :=
       1    1  5  0  0  1  0
       2    0  0  1  4  0  6
       3    1  6  0  1  0  0
       4    4  1  0  0  9  4
       5    0  1  0  5  0  1
       6    3  0  1  7  1  0;
       
end;


The output

>D:\Iniciação Científica\gusek\glpsol.exe --cover --clique --gomory --mir -m "minimiza.mod"   
GLPSOL: GLPK LP/MIP Solver, v4.44
Parameter(s) specified in the command line:
 --cover --clique --gomory --mir -m minimiza.mod
Reading model section from minimiza.mod...
Reading data section from minimiza.mod...
51 lines were read
Generating agrupamento...
Generating ContFluxo1...
Generating ContFluxo2...
Generating ContFluxo3...
Generating const...
Generating obj...
Model has been successfully generated
GLPK Integer Optimizer, v4.44
691 rows, 457 columns, 1317 non-zeros
457 integer variables, none of which are binary
Preprocessing...
PROBLEM HAS NO PRIMAL FEASIBLE SOLUTION
Time used:   0.0 secs
Memory used: 0.6 Mb (661481 bytes)
>Exit code: 0    Time: 0.231