一个比较有趣的题：推算今天星期几

((x == 1) == true)&&((x != 2) == false)||((x == 1) == false)&&((x != 2) == true)

(x == 1)&&(x == 2)||(x != 1)&&(x != 2)

function printDate(arr) {
        //param x ==>假如今天周几，用 x 去推算八个人的答案，num ==>计数器，x满足八个人的答案，则输出x
        var x,num;
        for(x = 1;x < 8;x++){//1 -- 7对每一天进行推算
            num = 0;
            for(var j = 0;j <　8; j++){
                //对每一天进行判断
                if(((x == arr[j][0])&&(x == arr[j][1]) || (x != arr[j][0])&&(x != arr[j][1]))){
                    num++;
                    //如果八个人都满足，输出x,并跳出本循环
                    if(num == 8){
                        console.log(x);
                        break;
                    }
                }
            }
        }
    }
    //八个人的答案组成的数组
    var arr1 = [[1,2],[2,6],[3,4],[5,1],[7,7],[1,5],[1,4],[4,2]];
    var arr2 = [[1,2],[1,2],[1,2],[1,2],[1,2],[1,2],[1,2],[1,2]];
    printDate(arr1);//7
    printDate(arr2);//3,4,5,6,7