Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revision Previous revision
aa:lab:decidability [2016/10/16 19:49]
dalex formatting
aa:lab:decidability [2016/11/01 12:07] (current)
pdmatei
Line 2: Line 2:
  
 We recall a few basic definitions. Let $math[M] be a Turing Machine over $\Sigma^*$ and $math[f:​\Sigma^*\rightarrow\{0,​1\}] be a decision problem. Then: We recall a few basic definitions. Let $math[M] be a Turing Machine over $\Sigma^*$ and $math[f:​\Sigma^*\rightarrow\{0,​1\}] be a decision problem. Then:
-  * $math[M] accepts $math[f] $math[\iff] $math[\forall w\in\Sigma^*:​ M(w) = 1 \iff f(w) = 1]+  * $math[M] accepts $math[f] $math[\iff] $math[\forall w\in\Sigma^*:​ M(w) = 1 \iff f(w) = 1] and $math[M(w) = \bot \text{ otherwise }]
   * $math[M] decides $math[f] $math[\iff] $math[M] accepts $math[f] and $math[M] halts for all inputs.   * $math[M] decides $math[f] $math[\iff] $math[M] accepts $math[f] and $math[M] halts for all inputs.