算法题目（二）

#include<stdio.h>
#include<math.h>
#include<stdbool.h>

bool flag = true;

//求base的正数absExp次幂
double PowerAbs(double base,unsigned int absExp)
{
	//递归退出的条件
	if(absExp == 0)
		return 1.0;
	if(absExp == 1)
		return base;
	
	//递归求次方
	double result = PowerAbs(base,absExp>>1);
		result *= result;
	//判断奇偶性
	if(absExp&1 == 1)
		result *= base;

	return result; 
}

//求base的exp次方
double Power(double base,int exp)
{
	//底数为0，指数为负数的情况
	if(fabs(base-0.0)<0.0000001 && exp<=0)
	{
		flag = false;
		return 0.0;
	}

	unsigned int absExp = (unsigned int)abs(exp);
	double result = PowerAbs(base,absExp);
	if(exp<0)
		result = 1.0/result;

	return result;
}

int main()
{
	int n,exp;
	double base;
	while(scanf("%d",&n) != EOF)
	{
		int i;
		for(i=0;i<n;i++)
		{
			//每次都要先将flag置为true
			flag = true;
			scanf("%lf %d",&base,&exp);
			double result = Power(base,exp);
			if(flag)
				printf("%.2ef\n",result);
			else
				printf("INF\n");
		}
	}
	return 0;
}

#include <stdio.h>
#include <stdlib.h>
#include <memory.h>


// 字符串number表示一个数字，在 number上增加1
// 如果做加法溢出，则返回true；否则为false
bool Increment(char* number)
{
    bool isOverflow = false;
    int nTakeOver = 0;
    int nLength = strlen(number);

    for(int i = nLength - 1; i >= 0; i --)
    {
        int nSum = number[i] - '0' + nTakeOver;
        if(i == nLength - 1)
            nSum ++;

        if(nSum >= 10)
        {
            if(i == 0)
                isOverflow = true;
            else
            {
                nSum -= 10;
                nTakeOver = 1;
                number[i] = '0' + nSum;
            }
        }
        else
        {
            number[i] = '0' + nSum;
            break;
        }
    }

    return isOverflow;
}


void PrintNumber(char* number)
{

    bool isBeginning0 = true;
    int nLength = strlen(number);

    for(int i = 0; i < nLength; ++ i)
    {
        if(isBeginning0 && number[i] != '0')
            isBeginning0 = false;

        if(!isBeginning0)
        {
            printf("%c", number[i]);
        }
    }

    printf("\n");
}

void Print1ToMaxOfNDigits(int n)
{
    if(n <= 0)
        return;

    char *number = new char[n + 1];
    memset(number, '0', n);
    number[n] = '\0';

    while(!Increment(number))
    {
        PrintNumber(number);
    }

    delete []number;
}


int main(){
    Print1ToMaxOfNDigits(2);
    return 0;
}

#include <iostream>
using namespace std;

typedef struct LNode{
    int value;
    LNode *next;
}LNode, *List;

void InsertList(List &l, int value)//头插入节点
{
    List head;
    LNode *p=new LNode;
    p->value=value;
    if(NULL==l)
        p->next=NULL;
    else
        p->next=l;
    l=p;
}

void PrintList(List l)//打印链表
{
    LNode *p=l;
    while(p)
    {
        cout<<p->value<<" ";
        p=p->next;
    }
    cout<<endl;
}

void DeleteNode(List &l, LNode *toBeDeleted)//删除链表l中的toBeDeleted节点
{
    LNode *p;
    if(!l || !toBeDeleted)
        return;

    if(l==toBeDeleted)//若删除的节点是表头
    {
        p=l->next;
        delete toBeDeleted ;
        l=p;
    }
    else
    {
        if(toBeDeleted->next==NULL)//若删除的节点是最后一个节点
        {
            p=l;
            while(p->next!=toBeDeleted)
                p=p->next;
            p->next=NULL;
            delete toBeDeleted;
        }
        else//删除节点是中间节点
        {
            p=toBeDeleted->next;
            toBeDeleted->value=p->value;
            toBeDeleted->next=p->next;
            delete p;

        }

    }

}

int main()
{
    List l=NULL;
    LNode *p;
    int n;
    InsertList(l, 3);
    InsertList(l, 7);
    InsertList(l, 12);
    InsertList(l, 56);
    InsertList(l, 33);
    InsertList(l, 78);
    InsertList(l, 20);
    InsertList(l, 89);

    PrintList(l);
    cout<<"请输入要删除的节点：";
    cin>>n;

    p=l;
    while(p->value!=n && p)
        p=p->next;

    if(!p)
    {
        cout<<"不存在这样的节点！"<<endl;
        return 0;
    }
    else
        DeleteNode(l, p);
    cout<<"删除后的链表：";
    PrintList(l);

    return 0;

}

struct ListNode
{
  int value;
  ListNode *next;
};

ListNode* FindKthToTail(ListNode* pListHead, unsigned int k)
{
    if(pListHead == NULL || k == 0)
        return NULL;

    ListNode *pAhead = pListHead;
    ListNode *pBehind = NULL;
    for(unsigned int i = 0; i < k - 1; ++ i)
    {
        if(pAhead->next != NULL)
            pAhead = pAhead->next;
        else
        {
            return NULL;
        }
    }
    pBehind = pListHead;
    while(pAhead->next != NULL)
    {
        pAhead = pAhead->next;
        pBehind = pBehind->next;
    }
    return pBehind;
}

void reverse(ListNode *head){
    ListNode* cur;
    ListNode* temp;
    cur = head->next;
    while(cur->next != NULL){
        temp = cur->next;
        cur->next = temp->next;
        temp->next = head->next;
        head->next = temp;
    }
    
    cur->next = head;//相当于成环
    head = cur->next->next;//新head变为原head的next
    cur->next->next=NULL;//断掉环
}

ListNode* Merge(ListNode* pHead1, ListNode* pHead2)
{
    if(pHead1==NULL||pHead2==NULL)
        return pHead1==NULL?pHead2:pHead1;
    
    ListNode *pHead=NULL; // 新链表
    ListNode *p1=pHead1;  // 定位链表1的结点
    ListNode *p2=pHead2;  // 定位链表2的结点
    ListNode *p=pHead;    // 
    
    while(p1!=NULL&&p2!=NULL)
    {
        ListNode *q= NULL;  // 
        if(p1->value <=p2->value) // 看看插哪个点
            q=p1;
        else
            q=p2;
        if(pHead ==NULL)//初次插入结点
        {
            p=q;
            (q==p1)?(p1=p1->next):(p2=p2->next);
            p->next = NULL;
            pHead=p;//这里很重要啊！！！
        }
        else
        {
            p->next=q;
            (q==p1)?(p1=p1->next):(p2=p2->next);
            p=p->next;
            p->next=NULL;
        }
    } // 有一边已经被选完了
    
    p->next= (p1==NULL)?p2:p1;
    return pHead;
}