You can not conclude here anything . This is fallacy of affirming the conclusion.
there will be flood. -> Lets say we write it as F
if it is raining for long -> R
if it is raining for long , there will be flood .-> R->F
Now we have
F
R->F
We can not conlude anything here. As we are affirming conclusion here, but it does not derive anything.
So we can say from above Two statements, " there will be flood." Same statement given to else, Nothing more.
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See you have statement p->q
Then if you say q is true.
p->q,q => This is fallacy of affirming the conclusion.You can not derive here.
Also this is called fallacy of converse. i.e. If you derive p, then it is because you are assuming q-> p, which is incorrect.
Second one ->
p->q,~p => Fallacy of denying the hypothesis, You can not derive anything here..
If you try to derive ~q, then you are saying that ~p->~q, which is incorrect. It is also called fallacy of inverse.