Finite State Machine Simulator
Simulate deterministic state transitions for an input string. Enter state,symbol,next-state rules and inspect the path and final state.
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Finite State Machine Simulator
Simulate deterministic state transitions for an input string. Enter state,symbol,next-state rules and inspect the path and final state.
Worked example
q0,0,q0 q0,1,q1 q1,0,q0 q1,1,q1 input = 1011; initial = q0
q0 → q1 → q0 → q1 → q1
Input and calculation
Enter each transition as current-state,input-character,next-state on its own line. Paste q0,0,q0; q0,1,q1; q1,0,q0; q1,1,q1 on four separate lines.
Set input string to 1011 and initial state to q0, then run. Expect q0 → q1 → q0 → q1 → q1, ending in q1. Check each transition against the table.
Limits
Use at most 200 rules and one Unicode code point per input symbol. Duplicate state-symbol rules or missing transitions cause errors. This deterministic simulator has no accepting-state field, epsilon transitions, minimization or diagram.
State names and the initial state are limited to 50 UTF-16 code units; the input string to 10000. Rule fields are trimmed, so whitespace alone cannot be an input symbol. Match the initial state exactly, including case, without surrounding spaces. An empty input returns the initial state unchanged. Missing transitions produce a general error, without the failing position or a partial path.
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