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| // Based on: https://x.com/ptrschmdtnlsn/status/1840765584398840233 | |
| #include <stdint.h> | |
| #include <stdio.h> | |
| #include <string.h> | |
| constexpr uint32_t N = 7; | |
| constexpr uint32_t M = 1u << N; | |
| constexpr uint32_t MaxNumStates = 6; | |
| void fmt_bits(char str[N+1], int32_t x) | |
| { | |
| uint32_t u; | |
| memcpy(&u, &x, sizeof(uint32_t)); | |
| for(int i = 0; i < N; ++i) | |
| { | |
| str[i] = u & (1u << i) ? '1' : '0'; | |
| } | |
| str[N] = '\0'; | |
| } | |
| int main() { | |
| constexpr uint32_t MaxDuration = 1u << (MaxNumStates - 2); | |
| uint32_t durations[M]; | |
| for(int32_t i = 0; i < M; ++i) | |
| { | |
| const int32_t m = i & -i; | |
| const int32_t j = 2 * (i & -i); | |
| char str_bits_i[N+1]; | |
| fmt_bits(str_bits_i, i); | |
| char str_bits_minus_i[N+1]; | |
| fmt_bits(str_bits_minus_i, -i); | |
| char str_bits_m[N+1]; | |
| fmt_bits(str_bits_m, m); | |
| printf("%2d: %s | %3d: %s | m: %s | j: %2d\n", i, str_bits_i, -i, str_bits_minus_i, str_bits_m, j); | |
| durations[i] = j < MaxDuration ? j : MaxDuration; | |
| } | |
| for(int32_t i = 0; i < M * 2; ++i) | |
| { | |
| printf("Frame %3d: 0 ", i); | |
| for(int32_t j = 0, n = i <= M-1 ? i : M-1; j <= n; ++j) | |
| { | |
| if(i < (j + durations[j])) | |
| { | |
| printf("%3d ", j); | |
| } | |
| } | |
| printf("\n"); | |
| } | |
| return 0; | |
| } |
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