二分模板

int search_1(int l, int r){
    while(l < r){
        int mid = l + r >> 1;
        if(array[mid] >= Find_Num)r = mid;  
        else l = mid + 1;
    }
    return r;//return l;此时l == r,为最左边的Find_Num下标
}

int search_2(int l, int r){
    while(l < r){
        int mid = l + r + 1 >> 1;
        if(array[mid] <= Find_Num)l = mid;
        else r = mid - 1;
    }
    return l;//return r;此时l == r,为最右边的Find_Num下标
}