River crossing problem | JavaScript Programming Project

{"id":28917,"student_id":10,"content":"// 人、狼、羊、菜\nvar statuss = [[false, false, false, false]];\nvar logs = [];\n\nfunction checkSafe (statuss) {\n    if (statuss[0] != statuss[1] \u0026\u0026 statuss[1] == statuss[2]) return false;\n    if (statuss[0] != statuss[2] \u0026\u0026 statuss[2] == statuss[3]) return false;\n    return true;\n}\n\nfunction checkRepeat (logs, clone) {\n    for (var i=0; i\u003clogs.length; i++) {\n        var l = logs[0];\n        if (l[0] == clone[0] \u0026\u0026 l[1] == clone[1] \u0026\u0026\n            l[2] == clone[2] \u0026\u0026 l[3] == clone[3]) {\n                return true;\n            }\n    }\n    return false;\n}\n\nfunction showSteps (s) {\n    while(s != undefined) {\n        console.log(s.toString());\n        s = s.from;\n    }\n}\n\nforever(function(){\n    if (statuss.length \u003c= 0) return;\n    \n    var s = statuss.shift();\n    logs.push(s);\n    \n    for (var i=1; i\u003c3; i++) {\n        if (s[i] == s[i]) {\n            var clone = s.slice();\n            clone[0] = !clone[0];\n            clone[i] = !clone[i];\n            if (checkSafe(clone) \u0026\u0026 !checkRepeat(logs, clone)) {\n                clone.form = s;\n                statuss.push(clone);\n            }\n            if (clone[0] \u0026\u0026 clone[1] \u0026\u0026 clone[2] \u0026\u0026 clone[3]) {\n                showSteps(clone);\n            }\n        }\n    }\n    var clone = s.slice();\n    clone[0] = !clone[0];\n    if (checkSafe(clone) \u0026\u0026 !checkRepeat(logs, clone)) {\n        clone.form = s;\n        statuss.push(clone);\n    }\n    if (clone[0] \u0026\u0026 clone[1] \u0026\u0026 clone[2] \u0026\u0026 clone[3]) {\n        showSteps(clone);\n        }\n});","created_at":"2018-05-16T11:28:53.813+08:00","updated_at":"2019-10-21T09:36:32.264+08:00","name":"River crossing problem","language":"javascript","screenshot":{"url":"/uploads/project/screenshot/28917/fd1ac05835b665cf0d7e3c5532c7c2d7.jpg"},"parent_id":2,"plugin":"","description":null,"note":null,"status":"public","like_student_ids":[],"is_featured":false,"views":517,"hashid":"9ygs5neq","is_content_changed":false,"review_status":"unsubmitted","submitted_at":null,"reviewed_at":null,"advise":null,"is_deleted":false}