Originally posted by: Lessi

I am not sure but the log did not show the optimal solution that cplex had found:

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Aggregator did 4 substitutions.
Reduced MIP has 11 rows, 11 columns, and 33 nonzeros.
Reduced MIP has 9 binaries, 0 generals, 0 SOSs, and 0 indicators.
Presolve time = 0.01 sec. (5.75 ticks)
Found incumbent of value 290.000000 after 0.01 sec. (6.60 ticks) => it found a feasible solution
Probing fixed 4 vars, tightened 0 bounds.
Probing time = 0.00 sec. (0.01 ticks)
Tried aggregator 2 times.
MIP Presolve eliminated 10 rows and 10 columns.
MIP Presolve modified 5 coefficients.
Aggregator did 1 substitutions.
All rows and columns eliminated.
Presolve time = 0.00 sec. (0.05 ticks)

Root node processing (before b&c):
  Real time             =    0.01 sec. (6.84 ticks)
Sequential b&c:
  Real time             =    0.00 sec. (0.00 ticks)
                          ------------
Total (root+branch&cut) =    0.01 sec. (6.84 ticks)

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It does not show the optimal solution that cplex found, which is 310 (via the command cout<<cplexFull.getObjValue() << '\t' << cplexFull.getBestObjValue()<<endl;) may be it is because the problem is too simple to solve.
 

This is expected. As you can see, your model presolve to nothing:

All rows and columns eliminated.

In that case CPLEX will not show any message for the solution that is implied by that. Indeed, your model is too easy :-)