45 lines
1.2 KiB
Text
45 lines
1.2 KiB
Text
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global lfsr_iterations = 5;
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global lfsr_length = 4;
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global lfsr_init_values = new bool[]{true, false, true, false};
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bool xor(bool x, bool y) {
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return (x & !y) | (!x & y);
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}
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string string_of_bool(bool b) {
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if (b) { return "T"; }
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else { return "F"; }
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}
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void print_lfsr(bool[] lfsr_register, int len) {
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for (var i = 0; i < len; i = i + 1;) {
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print_string(string_of_bool(lfsr_register[i]));
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}
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return;
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}
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int program(int argc, string[] argv) {
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/* Initialize the working register */
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var lfsr_register = new bool[lfsr_length];
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for (var i=0; i < lfsr_length; i=i+1;) {
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lfsr_register[i] = lfsr_init_values[i];
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}
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/* Do the computations */
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for (var i = 0; i < lfsr_iterations; i = i + 1;) {
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var new_first =
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xor(lfsr_register[lfsr_length - 1], lfsr_register[lfsr_length - 2]);
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for (var j = lfsr_length - 1; j > 0; j = j - 1;) {
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lfsr_register[j] = lfsr_register[j - 1];
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}
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lfsr_register[0] = new_first;
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}
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/* Print the initial and final bool arrays with a space separator */
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print_lfsr(lfsr_init_values, lfsr_length);
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print_string(" ");
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print_lfsr(lfsr_register, lfsr_length);
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return 0;
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}
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