# python -sage

Hi

I am have an optimization problem, when I run it for small amount of input it is ok , but for large input, It give : KeyboardInterrupt I will appreciate if one can help me ?

the error is

```
Traceback (most recent call last):
File "final2.py", line 181, in <module>
scheduling.add_constraint(Sum(A[s][d][k][o][p][t] for p in range (_sage_const_0 ,V)) <=_sage_const_1 )
File "mip.pyx", line 2168, in sage.numerical.mip.Sum (sage/numerical/mip.c:12041)
File "final2.py", line 181, in <genexpr>
scheduling.add_constraint(Sum(A[s][d][k][o][p][t] for p in range (_sage_const_0 ,V)) <=_sage_const_1 )
KeyboardInterrupt
```

Typically a `KeyboardInterrupt` is just that. Did you do `Ctrl-C` or something? Just asking, as presumably you wouldn't have asked if that was the case.

Also, if you can either post or put a link to the full code, or construct a small example, that would really help; at this point it's very hard to tell what is wrong, if anything.

I think some timers use KeyboardInterrupt as the signal; maybe that's what's going on.