【数据结构】二分法查找

 

二分法查找：

Position BinarySearch(List L, ElementType X)
{
    Position Left, Right, Mid;
    Left = 1;
    Right = L->Last;
    while(Left <= Right){
        Mid = (Left + Right) / 2;
        if(X > L->Data[Mid])
            Left = Mid + 1;
        else if(X < L->Data[Mid])
            Right = Mid - 1;
        else
            return Mid;
    }
    return NotFound;
}