File size: 914 Bytes
a9e7957 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 | {
"name": "costas_array_n9__v7_nh",
"problem_type": "costas_array",
"params": {
"n": 9
},
"prompt": "Find a Costas array of order 9: place 9 marks on an 9x9 grid, one per row and one per column, such that all 9*(8)/2 displacement vectors (dr, dc) between pairs of marks (with dc > 0) are pairwise distinct.\n\nReturn x as a list of 9 integers in 0..8, where x[c] is the row of the mark in column c (permutation), or state \"UNSATISFIABLE\" if no such array exists.",
"satisfiable": true,
"solution": {
"x": [
1,
7,
3,
6,
8,
2,
0,
5,
4
]
},
"difficulty": {
"solve_time_ms": 932.4,
"search_space": 362880,
"num_variables": 9,
"num_constraints": 10,
"num_edges": -1,
"backend": "pycsp",
"solve_tier": "medium",
"solve_pct_global": 60.71,
"solve_pct_type": 50.0
},
"partial_assignment": null
}
|