[Ybt OJ] [String Algorithm Chapter 1] String Processing

$「$ String Algorithm$"$ No.1 1Chapter$1$ String Processing
Directory:

A.数字反转
B.位移包换
C.单词替换
D.字符串环
E.生日相同

This question is too shabby...

$A.$ Example$1$ number inversion

analysis:

You can directly use the function $strrev\; do$ it again$0$
can also bedirectly converted

CODE：

#include<iostream>
#include<cstdio>
#pragma GCC optimize(2)
using namespace std;
int numa,numb;
int main(){
    
    
    for(scanf("%d",&numa);numa!=0;numa/=10)
        numb=numb*10+numa%10;
    printf("%d",numb);
    return 0;
} 

$B.$ Example$2$ displacement replacement

analysis:

A cough question Just copy
the longest string and find the short one .

CODE：

#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstring>
#include<cmath>
#include<queue> 
//#pragma GCC optimize(2)
#define reg register 
using namespace std;
typedef long long ll;
typedef double db;
string s1,s2;
int main(){
    
    
	cin>>s1>>s2;
	if(s1.length()<s2.length()) swap(s1,s2);  //找最长
	s1+=s1;  //复制
	if(s1.find(s2)==-1) puts("false");  //查找
	else puts("true");	
	return 0;
} 

$C.$ Example$3$ word replacement

analysis:

In fact, you can enter each word separately and then directly judge the equality and replace it .

CODE：

#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstring>
#include<cmath>
#include<queue> 
#pragma GCC optimize(2)
#define reg register 
using namespace std;
typedef long long ll;
typedef double db;
string s[101],a,b;
void work(int x)
{
    
    
	if(a==s[x]) cout<<b<<" ";  //匹配 替换
	else cout<<s[x]<<" ";  //原样输出
}
int main(){
    
    
	int n=0;
	char ch;
	do{
    
    
		cin>>s[++n];//cout<<"XXX ";
		scanf("%c",&ch);
	}while(ch==' ');
	cin>>a>>b;
	for(reg int i=1;i<=n;i++)
		work(i);
	return 0;
} 

$D.$ Example$4$ string loop

analysis:

Can $mod$ string lengthto update thematching position,you don't need tocopytwo strings directly.

CODE：

#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstring>
#include<cmath>
#include<queue> 
//#pragma GCC optimize(2)
#define reg register 
using namespace std;
typedef long long ll;
typedef double db;
string s1,s2;
int ans,cnt;
int main(){
    
    
	cin>>s1>>s2;
	//s1+=s1;
	//s2+=s2;
	//if(s1.length()<s2.length()) swap(s1,s2);
	int minlen=min(s1.length(),s2.length());
	for(int i=0;i<s1.length();i++)
		for(int j=0;j<s2.length();j++)
		{
    
    
			int k=i,l=j;
			cnt=0;
			while(s1[k]==s2[l])  //公共
			{
    
    
				cnt++;
				k=(k+1)%s1.length();  //向后更新
				l=(l+1)%s2.length();
				if(cnt>=minlen) break;
			}
			ans=max(ans,cnt);
		}
	printf("%d",ans);
	return 0;
} 

$E.$ Example55Same birthday on$5$

analysis:

As for the consideration of equality, it is better to directly consider inequality and then continue to compare and judge.
Therefore, if it is not the same month and the same day , directly wrap and re-output a line, and the
rest will follow the output name . Note $sort$
$ps:$ Don't use$char$ array with$string$

CODE：

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#define MAXN 100005
using namespace std;
struct st{
    
    
    int month,day;
    string name;
    bool operator<(const st& a)const{
    
    
        if(month!=a.month) return month<a.month;
        if(day!=a.day) return day<a.day;  //排序
        if(name.length()!=a.name.length()) return name.length()<a.name.length();  
        return name<a.name;
    }
}a[MAXN];
int n,next_month,next_day,k;
int main()
{
    
    
    scanf("%d",&n);
    for(int i=1;i<=n;i++)
    {
    
    
    	cin>>a[i].name;
    	scanf("%d%d",&a[i].month,&a[i].day);
	}
    sort(a+1,a+n+1);
    next_month=a[1].month,next_day=a[1].day;
    for(int i=2;i<=n;i++)
    {
    
    
        if(a[i].month!=next_month||a[i].day!=next_day)
        {
    
    
            next_month=a[i].month;
            next_day=a[i].day;
        }else k++;  //有相同生日
    }
    if(k)
    {
    
    
        printf("%d %d ",a[1].month,a[1].day);
        cout<<a[1].name<<" ";
        next_month=a[1].month,next_day=a[1].day;
        for(int i=2;i<=n;i++)
        {
    
    
            if(a[i].month!=next_month||a[i].day!=next_day)  //不是同生日
            {
    
    
            	printf("\n");
                next_month=a[i].month;
                next_day=a[i].day;
                printf("%d %d ",next_month,next_day);  //重新输出一行
                cout<<a[i].name<<" ";
            }
            else cout<<a[i].name<<" ";  //跟着输出
        }
    }else puts("None");
    return 0;
}