1.delete方法:delete arr[1]這種方式數組長度不變,此時arr[1]變為undefined了,但是也有好處原來數組的索引也保持不變,此時要遍曆數組元素可以才用for(index in arr)document.write(’arr[’+index+’]=’+arr[index]);這種遍曆方式跳過其中undefined的元素*
專題二(分治)131:19:34725:00:00OverviewProblemStatusRankA B C D E F G H ID - 4 Values whose Sum is 0Time Limit:15000MS Memory Limit:228000KB 64bit IO Format:%I64d & %I64uSubmit StatusDescriptionThe SUM problem can be formulated as follows:
A. Eugeny and ArrayTime Limit:2000msCase Time Limit:2000msMemory Limit:262144KB64-bit integer IO format:%I64d Java class name:(Any)SubmitStatusPID: 29452 Font Size:Eugeny has arraya = a1, a2, ..., an, consisting ofn integers. Each
要擷取當前頁面的捲軸縱座標位置,用:document.documentElement.scrollTop;而不是:document.body.scrollTop;documentElement 對應的是 html 標籤,而 body 對應的是 body 標籤。在標準w3c下,document.body.scrollTop恒為0,需要用document.documentElement.scrollTop來代替;如果你想定位滑鼠相對於頁面的絕對位置時,你會發現google裡面1000篇文章裡面有99
E - Burning Midnight OilTime Limit:2000MS Memory Limit:262144KB 64bit IO Format:%I64d & %I64uSubmit StatusDescriptionOne day a highly important task was commissioned to Vasya — writing a program in a night. The program consists
A - Expanding RodsTime Limit:1000MS Memory Limit:30000KB 64bit IO Format:%I64d & %I64uSubmit StatusDescriptionWhen a thin rod of length L is heated n degrees, it expands to a new length L'=(1+n*C)*L, where C is the coefficient of heat