{
    "name": "Sudoku 4x4",
    "background": "http://www.sudokuweb.org/easy-sudoku-4x4-for-kids/",
    "constraints": {
        "unique11": {
            "equal": 1
        },
        "unique12": {
            "equal": 1
        },
        "unique13": {
            "equal": 1
        },
        "unique14": {
            "equal": 1
        },
        "unique21": {
            "equal": 1
        },
        "unique22": {
            "equal": 1
        },
        "unique23": {
            "equal": 1
        },
        "unique24": {
            "equal": 1
        },
        "unique31": {
            "equal": 1
        },
        "unique32": {
            "equal": 1
        },
        "unique33": {
            "equal": 1
        },
        "unique34": {
            "equal": 1
        },
        "unique41": {
            "equal": 1
        },
        "unique42": {
            "equal": 1
        },
        "unique43": {
            "equal": 1
        },
        "unique44": {
            "equal": 1
        },
        "oncePerRow11": {
            "equal": 1
        },
        "oncePerColumn11": {
            "equal": 1
        },
        "oncePerRow12": {
            "equal": 1
        },
        "oncePerColumn12": {
            "equal": 1
        },
        "oncePerRow13": {
            "equal": 1
        },
        "oncePerColumn13": {
            "equal": 1
        },
        "oncePerRow14": {
            "equal": 1
        },
        "oncePerColumn14": {
            "equal": 1
        },
        "oncePerRow21": {
            "equal": 1
        },
        "oncePerColumn21": {
            "equal": 1
        },
        "oncePerRow22": {
            "equal": 1
        },
        "oncePerColumn22": {
            "equal": 1
        },
        "oncePerRow23": {
            "equal": 1
        },
        "oncePerColumn23": {
            "equal": 1
        },
        "oncePerRow24": {
            "equal": 1
        },
        "oncePerColumn24": {
            "equal": 1
        },
        "oncePerRow31": {
            "equal": 1
        },
        "oncePerColumn31": {
            "equal": 1
        },
        "oncePerRow32": {
            "equal": 1
        },
        "oncePerColumn32": {
            "equal": 1
        },
        "oncePerRow33": {
            "equal": 1
        },
        "oncePerColumn33": {
            "equal": 1
        },
        "oncePerRow34": {
            "equal": 1
        },
        "oncePerColumn34": {
            "equal": 1
        },
        "oncePerRow41": {
            "equal": 1
        },
        "oncePerColumn41": {
            "equal": 1
        },
        "oncePerRow42": {
            "equal": 1
        },
        "oncePerColumn42": {
            "equal": 1
        },
        "oncePerRow43": {
            "equal": 1
        },
        "oncePerColumn43": {
            "equal": 1
        },
        "oncePerRow44": {
            "equal": 1
        },
        "oncePerColumn44": {
            "equal": 1
        },
        "oncePerBlock001": {
            "equal": 1
        },
        "oncePerBlock002": {
            "equal": 1
        },
        "oncePerBlock003": {
            "equal": 1
        },
        "oncePerBlock004": {
            "equal": 1
        },
        "oncePerBlock011": {
            "equal": 1
        },
        "oncePerBlock012": {
            "equal": 1
        },
        "oncePerBlock013": {
            "equal": 1
        },
        "oncePerBlock014": {
            "equal": 1
        },
        "oncePerBlock101": {
            "equal": 1
        },
        "oncePerBlock102": {
            "equal": 1
        },
        "oncePerBlock103": {
            "equal": 1
        },
        "oncePerBlock104": {
            "equal": 1
        },
        "oncePerBlock111": {
            "equal": 1
        },
        "oncePerBlock112": {
            "equal": 1
        },
        "oncePerBlock113": {
            "equal": 1
        },
        "oncePerBlock114": {
            "equal": 1
        }
    },
    "variables": {
        "x111": {
            "unique11": 1,
            "oncePerRow11": 1,
            "oncePerColumn11": 1,
            "oncePerBlock001": 1
        },
        "x112": {
            "unique11": 1,
            "oncePerRow12": 1,
            "oncePerColumn12": 1,
            "oncePerBlock002": 1
        },
        "x113": {
            "unique11": 1,
            "oncePerRow13": 1,
            "oncePerColumn13": 1,
            "oncePerBlock003": 1
        },
        "x114": {
            "unique11": 1,
            "oncePerRow14": 1,
            "oncePerColumn14": 1,
            "oncePerBlock004": 1
        },
        "x121": {
            "unique12": 1,
            "oncePerRow11": 1,
            "oncePerColumn21": 1,
            "oncePerBlock001": 1
        },
        "x122": {
            "unique12": 1,
            "oncePerRow12": 1,
            "oncePerColumn22": 1,
            "oncePerBlock002": 1
        },
        "x123": {
            "unique12": 1,
            "oncePerRow13": 1,
            "oncePerColumn23": 1,
            "oncePerBlock003": 1
        },
        "x124": {
            "unique12": 1,
            "oncePerRow14": 1,
            "oncePerColumn24": 1,
            "oncePerBlock004": 1
        },
        "x131": {
            "unique13": 1,
            "oncePerRow11": 1,
            "oncePerColumn31": 1,
            "oncePerBlock011": 1
        },
        "x132": {
            "unique13": 1,
            "oncePerRow12": 1,
            "oncePerColumn32": 1,
            "oncePerBlock012": 1
        },
        "x133": {
            "unique13": 1,
            "oncePerRow13": 1,
            "oncePerColumn33": 1,
            "oncePerBlock013": 1
        },
        "x134": {
            "unique13": 1,
            "oncePerRow14": 1,
            "oncePerColumn34": 1,
            "oncePerBlock014": 1
        },
        "x141": {
            "unique14": 1,
            "oncePerRow11": 1,
            "oncePerColumn41": 1,
            "oncePerBlock011": 1
        },
        "x142": {
            "unique14": 1,
            "oncePerRow12": 1,
            "oncePerColumn42": 1,
            "oncePerBlock012": 1
        },
        "x143": {
            "unique14": 1,
            "oncePerRow13": 1,
            "oncePerColumn43": 1,
            "oncePerBlock013": 1
        },
        "x144": {
            "unique14": 1,
            "oncePerRow14": 1,
            "oncePerColumn44": 1,
            "oncePerBlock014": 1
        },
        "x211": {
            "unique21": 1,
            "oncePerColumn11": 1,
            "oncePerRow21": 1,
            "oncePerBlock001": 1
        },
        "x212": {
            "unique21": 1,
            "oncePerColumn12": 1,
            "oncePerRow22": 1,
            "oncePerBlock002": 1
        },
        "x213": {
            "unique21": 1,
            "oncePerColumn13": 1,
            "oncePerRow23": 1,
            "oncePerBlock003": 1
        },
        "x214": {
            "unique21": 1,
            "oncePerColumn14": 1,
            "oncePerRow24": 1,
            "oncePerBlock004": 1
        },
        "x221": {
            "unique22": 1,
            "oncePerRow21": 1,
            "oncePerColumn21": 1,
            "oncePerBlock001": 1
        },
        "x222": {
            "unique22": 1,
            "oncePerRow22": 1,
            "oncePerColumn22": 1,
            "oncePerBlock002": 1
        },
        "x223": {
            "unique22": 1,
            "oncePerRow23": 1,
            "oncePerColumn23": 1,
            "oncePerBlock003": 1
        },
        "x224": {
            "unique22": 1,
            "oncePerRow24": 1,
            "oncePerColumn24": 1,
            "oncePerBlock004": 1
        },
        "x231": {
            "unique23": 1,
            "oncePerRow21": 1,
            "oncePerColumn31": 1,
            "oncePerBlock011": 1
        },
        "x232": {
            "unique23": 1,
            "oncePerRow22": 1,
            "oncePerColumn32": 1,
            "oncePerBlock012": 1
        },
        "x233": {
            "unique23": 1,
            "oncePerRow23": 1,
            "oncePerColumn33": 1,
            "oncePerBlock013": 1
        },
        "x234": {
            "unique23": 1,
            "oncePerRow24": 1,
            "oncePerColumn34": 1,
            "oncePerBlock014": 1
        },
        "x241": {
            "unique24": 1,
            "oncePerRow21": 1,
            "oncePerColumn41": 1,
            "oncePerBlock011": 1
        },
        "x242": {
            "unique24": 1,
            "oncePerRow22": 1,
            "oncePerColumn42": 1,
            "oncePerBlock012": 1
        },
        "x243": {
            "unique24": 1,
            "oncePerRow23": 1,
            "oncePerColumn43": 1,
            "oncePerBlock013": 1
        },
        "x244": {
            "unique24": 1,
            "oncePerRow24": 1,
            "oncePerColumn44": 1,
            "oncePerBlock014": 1
        },
        "x311": {
            "unique31": 1,
            "oncePerColumn11": 1,
            "oncePerRow31": 1,
            "oncePerBlock101": 1
        },
        "x312": {
            "unique31": 1,
            "oncePerColumn12": 1,
            "oncePerRow32": 1,
            "oncePerBlock102": 1
        },
        "x313": {
            "unique31": 1,
            "oncePerColumn13": 1,
            "oncePerRow33": 1,
            "oncePerBlock103": 1
        },
        "x314": {
            "unique31": 1,
            "oncePerColumn14": 1,
            "oncePerRow34": 1,
            "oncePerBlock104": 1
        },
        "x321": {
            "unique32": 1,
            "oncePerColumn21": 1,
            "oncePerRow31": 1,
            "oncePerBlock101": 1
        },
        "x322": {
            "unique32": 1,
            "oncePerColumn22": 1,
            "oncePerRow32": 1,
            "oncePerBlock102": 1
        },
        "x323": {
            "unique32": 1,
            "oncePerColumn23": 1,
            "oncePerRow33": 1,
            "oncePerBlock103": 1
        },
        "x324": {
            "unique32": 1,
            "oncePerColumn24": 1,
            "oncePerRow34": 1,
            "oncePerBlock104": 1
        },
        "x331": {
            "unique33": 1,
            "oncePerRow31": 1,
            "oncePerColumn31": 1,
            "oncePerBlock111": 1
        },
        "x332": {
            "unique33": 1,
            "oncePerRow32": 1,
            "oncePerColumn32": 1,
            "oncePerBlock112": 1
        },
        "x333": {
            "unique33": 1,
            "oncePerRow33": 1,
            "oncePerColumn33": 1,
            "oncePerBlock113": 1
        },
        "x334": {
            "unique33": 1,
            "oncePerRow34": 1,
            "oncePerColumn34": 1,
            "oncePerBlock114": 1
        },
        "x341": {
            "unique34": 1,
            "oncePerRow31": 1,
            "oncePerColumn41": 1,
            "oncePerBlock111": 1
        },
        "x342": {
            "unique34": 1,
            "oncePerRow32": 1,
            "oncePerColumn42": 1,
            "oncePerBlock112": 1
        },
        "x343": {
            "unique34": 1,
            "oncePerRow33": 1,
            "oncePerColumn43": 1,
            "oncePerBlock113": 1
        },
        "x344": {
            "unique34": 1,
            "oncePerRow34": 1,
            "oncePerColumn44": 1,
            "oncePerBlock114": 1
        },
        "x411": {
            "unique41": 1,
            "oncePerColumn11": 1,
            "oncePerRow41": 1,
            "oncePerBlock101": 1
        },
        "x412": {
            "unique41": 1,
            "oncePerColumn12": 1,
            "oncePerRow42": 1,
            "oncePerBlock102": 1
        },
        "x413": {
            "unique41": 1,
            "oncePerColumn13": 1,
            "oncePerRow43": 1,
            "oncePerBlock103": 1
        },
        "x414": {
            "unique41": 1,
            "oncePerColumn14": 1,
            "oncePerRow44": 1,
            "oncePerBlock104": 1
        },
        "x421": {
            "unique42": 1,
            "oncePerColumn21": 1,
            "oncePerRow41": 1,
            "oncePerBlock101": 1
        },
        "x422": {
            "unique42": 1,
            "oncePerColumn22": 1,
            "oncePerRow42": 1,
            "oncePerBlock102": 1
        },
        "x423": {
            "unique42": 1,
            "oncePerColumn23": 1,
            "oncePerRow43": 1,
            "oncePerBlock103": 1
        },
        "x424": {
            "unique42": 1,
            "oncePerColumn24": 1,
            "oncePerRow44": 1,
            "oncePerBlock104": 1
        },
        "x431": {
            "unique43": 1,
            "oncePerColumn31": 1,
            "oncePerRow41": 1,
            "oncePerBlock111": 1
        },
        "x432": {
            "unique43": 1,
            "oncePerColumn32": 1,
            "oncePerRow42": 1,
            "oncePerBlock112": 1
        },
        "x433": {
            "unique43": 1,
            "oncePerColumn33": 1,
            "oncePerRow43": 1,
            "oncePerBlock113": 1
        },
        "x434": {
            "unique43": 1,
            "oncePerColumn34": 1,
            "oncePerRow44": 1,
            "oncePerBlock114": 1
        },
        "x441": {
            "unique44": 1,
            "oncePerRow41": 1,
            "oncePerColumn41": 1,
            "oncePerBlock111": 1
        },
        "x442": {
            "unique44": 1,
            "oncePerRow42": 1,
            "oncePerColumn42": 1,
            "oncePerBlock112": 1
        },
        "x443": {
            "unique44": 1,
            "oncePerRow43": 1,
            "oncePerColumn43": 1,
            "oncePerBlock113": 1
        },
        "x444": {
            "unique44": 1,
            "oncePerRow44": 1,
            "oncePerColumn44": 1,
            "oncePerBlock114": 1
        }
    },
    "binaries": {
        "x111": 1,
        "x112": 1,
        "x113": 1,
        "x114": 1,
        "x121": 1,
        "x122": 1,
        "x123": 1,
        "x124": 1,
        "x131": 1,
        "x132": 1,
        "x133": 1,
        "x134": 1,
        "x141": 1,
        "x142": 1,
        "x143": 1,
        "x144": 1,
        "x211": 1,
        "x212": 1,
        "x213": 1,
        "x214": 1,
        "x221": 1,
        "x222": 1,
        "x223": 1,
        "x224": 1,
        "x231": 1,
        "x232": 1,
        "x233": 1,
        "x234": 1,
        "x241": 1,
        "x242": 1,
        "x243": 1,
        "x244": 1,
        "x311": 1,
        "x312": 1,
        "x313": 1,
        "x314": 1,
        "x321": 1,
        "x322": 1,
        "x323": 1,
        "x324": 1,
        "x331": 1,
        "x332": 1,
        "x333": 1,
        "x334": 1,
        "x341": 1,
        "x342": 1,
        "x343": 1,
        "x344": 1,
        "x411": 1,
        "x412": 1,
        "x413": 1,
        "x414": 1,
        "x421": 1,
        "x422": 1,
        "x423": 1,
        "x424": 1,
        "x431": 1,
        "x432": 1,
        "x433": 1,
        "x434": 1,
        "x441": 1,
        "x442": 1,
        "x443": 1,
        "x444": 1
    },
    "expects": {
        "result": 0,
        "x111": 1,
        "x122": 1,
        "x134": 1,
        "x143": 1,
        "x213": 1,
        "x224": 1,
        "x231": 1,
        "x242": 1,
        "x312": 1,
        "x321": 1,
        "x333": 1,
        "x344": 1,
        "x414": 1,
        "x423": 1,
        "x432": 1,
        "x441": 1,
        "feasible": true
    }
}
