[Gym-101341B](KMP)(水）Pursuing the Happiness

求一个串中是否有happiness，如果有，交换两个字符，是否还能找到happiness，如果还能，输出NO，否则输出YES，然后输出交换的两个字符的下标，情况不唯一。

水题一道，当时写时，数组开小了一倍，runtime error on test 14 好多次，一脸蒙逼。。。

代码写的很冗长，思路很简单。

分情况讨论，

ans==0时，找交换的两个位

ans==1时，直接交换pos和pos+1就行了

ans==2时，交换pos1和pos2+1就行了

ans>2时，NO；

////  main.cpp//  160929////  Created by 刘哲 on 17/4/30.//  Copyright © 2016年 my_code. All rights reserved.//  卧槽，这代码写死我了//#include <bits/stdc++.h>#include <iostream>#include <algorithm>#include <cstdio>#include <cmath>#include <cstring>#include <string>#include <string.h>#include <map>#include <set>#include <queue>#include <deque>#include <list>#include <bitset>#include <stack>#include <stdlib.h>#define lowbit(x) (x&-x)typedef long long ll;using namespace std;char a[200000+10],b[10]="happiness";int p[200000+10],n,m,ans;void fail(){    int i,j=-1;    p[0]=-1;    for(i=1;i<m;i++)    {        while(j>=0&&b[j+1]!=b[i])  j=p[j];        if(b[i]==b[j+1])  j++;        p[i]=j;    }}int kmp(){    int i,j=-1;    ans=0;    for(i=0;i<n;i++)    {                while(j>=0&&b[j+1]!=a[i])   j=p[j];        if(a[i]==b[j+1])  j++;        if(j==m-1)        {            ans++;            j=-1;        }    }    return ans;}int main(){    scanf("%s",a);    string s = a;    n=strlen(a);    m=9;    fail();    int ans = kmp();    // printf("%d\n",kmp());    if(ans>2)        cout<<"NO"<<endl;    else    {        cout<<"YES"<<endl;        if(ans==0)        {            for(int i=0;i<n;i++)                for(int j=i+1;j<n;j++)                {                    swap(a[i],a[j]);                    if(!kmp())                    {                        cout<<i+1<<' '<<j+1<<endl;                        return 0;                    }                    swap(a[i],a[j]);                }        }        else if(ans==1)        {            int pos = s.find(b);            for(int i=pos;i<pos+9;i++)                for(int j=pos;j<pos+9;j++)                {                    swap(a[i],a[j]);                    if(!kmp())                    {                        cout<<i+1<<' '<<j+1<<endl;                        return 0;                    }                    swap(a[i],a[j]);                    continue;                }        }        else  //2        {            int pos1 = s.find(b);            int pos2 = s.rfind(b);            for(int i=pos1;i<pos1+9;i++)                for(int j=pos2;j<pos2+9;j++)                {                    swap(a[i],a[j]);                    if(!kmp())                    {                        cout<<i+1<<' '<<j+1<<endl;                        return 0;                    }                    swap(a[i],a[j]);                    continue;                }        }    }    return 0;}

////  main.cpp//  160929////  Created by 刘哲 on 17/4/30.//  Copyright © 2016年 my_code. All rights reserved.//  卧槽，这代码写死我了//#include <bits/stdc++.h>#include <iostream>#include <algorithm>#include <cstdio>#include <cmath>#include <cstring>#include <string>#include <string.h>#include <map>#include <set>#include <queue>#include <deque>#include <list>#include <bitset>#include <stack>#include <stdlib.h>#define lowbit(x) (x&-x)typedef long long ll;using namespace std;char a[200000+10],b[10]="happiness";int p[200000+10],n,m,ans;void fail(){    int i,j=-1;    p[0]=-1;    for(i=1;i<m;i++)    {        while(j>=0&&b[j+1]!=b[i])  j=p[j];        if(b[i]==b[j+1])  j++;        p[i]=j;    }}int kmp(){    int i,j=-1;    ans=0;    for(i=0;i<n;i++)    {                while(j>=0&&b[j+1]!=a[i])   j=p[j];        if(a[i]==b[j+1])  j++;        if(j==m-1)        {            ans++;            j=-1;        }    }    return ans;}int main(){    scanf("%s",a);    string s = a;    n=strlen(a);    m=9;    fail();    int ans = kmp();    // printf("%d\n",kmp());    if(ans>2)        cout<<"NO"<<endl;    else    {        //cout<<"YES"<<endl;        if(ans==0)        {            for(int i=0;i<n;i++)                for(int j=i+1;j<n;j++)                {                    swap(a[i],a[j]);                    if(!kmp())                    {                        cout<<"YES"<<endl<<i+1<<' '<<j+1<<endl;                        return 0;                    }                    if(i==j==n-1)                    {                        cout<<"NO"<<endl;                        return 0;                    }                    swap(a[i],a[j]);                }        }        else if(ans==1)        {            int pos = s.find(b);            for(int i=0;i<n;i++)                for(int j=pos;j<pos+9;j++)                {                    swap(a[i],a[j]);                    if(!kmp())                    {                        cout<<"YES"<<endl<<i+1<<' '<<j+1<<endl;                        return 0;                    }                    if(i==n-1&&j==pos+8)                    {                        cout<<"NO"<<endl;                        return 0;                    }                    swap(a[i],a[j]);                    continue;                }        }        else  //2        {            int pos1 = s.find(b);            int pos2 = s.rfind(b);            for(int i=pos1;i<pos1+9;i++)                for(int j=pos2;j<pos2+9;j++)                {                    swap(a[i],a[j]);                    if(!kmp())                    {                        cout<<"YES"<<endl<<i+1<<' '<<j+1<<endl;                        return 0;                    }                    if(i==pos1+8&&j==pos2+8)                    {                        cout<<"NO"<<endl;                        return 0;                    }                    swap(a[i],a[j]);                    continue;                }        }    }    return 0;}