#define strmax 100
#include <iostream.h>
#include <cstring>
class string
{
char line[100];
int x,y;
public:
string(char *);
void print();
void turn();
int strlength();
void substring(unsigned,unsigned);
void insert(int,char *);
void index(char *);
void replace(char *,char *);
void strempty();
string operator = (string s);
string operator + (string s);
void operator <= (string s1);//判斷字符竄長度
void operator == (string s1);//字符竄相等
void operator != (string s1);//字符竄不相等
char operator [] (int pos);
};
//===============================================================
string::string(char *n)
{
strcpy(line,n);
}
//===============================================================
void string::print()
{
cout<< line;
}
//===============================================================
void string::turn()
{
int i,len=strlen(line);
for(i=0;i<len;i++)
{
if(line[i]>=97&&line[i]<=122)
{
line[i]-=32;
cout<< line[i];
}
else
{
cout<< line[i];
}
}
}
//===============================================================
int string::strlength()
{
return strlen(line);
}
//===============================================================
void string::substring(unsigned pos,unsigned len)
{
if(pos > strlen(line))
cout<<"Error!";
else
{
if((strlen(line)-pos) < len)
len=strlen(line)-pos;
cout<<"The substring is:";
unsigned i=pos+len;
for(pos;pos<i;pos++)
{
cout<< line[pos-1];
}
}
}
//===============================================================
void string::insert(int pos,char *p)
{
char p1[64];
char p2[64];
strcpy(p1,p);
cout<<"The line which will be insert is:"<<p1;
int l=strlen (p1);
int m=0;
int c=0;
for(int b=pos-1;b<64;b++,c++)
{
p2[c]=line[b];
}
for(int a=pos-1;a<pos+l;a++,m++)
{
line[a]=p1[m];
}
strcat(line,p2);
cout<<endl<<"The line after inserting is:"<<line;
}
//===============================================================
void string::index(char *n)
{
char *p;
char n1[100];
char n2[100];
strcpy(n1,line);
strcpy(n2,n);
p=strstr(n1,n2);
int l;
l=strlen(n1);
cout<<"The words you want to find is:"<<n;
if(p)
{
strcpy(n2,p);
for(int i=0;i<l;i++)
{
if(n1[i]==n2[0])
{
cout<<endl<<"The position of the words which you wanted is "<<i+1;
break;
}
}
}
else
{
cout<<endl<<"There isn't the words which you wanted.";
}
}
//===============================================================
void string::replace(char *q,char *p)//q被替換串，p替換串
{
char p1[100];
char p2[100];
char p3[100];
strcpy(p1,line);
strcpy(p2,p);
strcpy(p3,q);
p=strstr(p1,p3);
if(p)
{
int i,j;
int lp=strlen(p);
int lp1=strlen(p1);
int lp2=strlen(p2);
int lp3=strlen(p3);
cout<<"The sourse string is : "<<line<<endl<<"You want to change : "<<p3;
for(i=lp1-lp,j=0;j<lp2;i++,j++)
line[i]=p2[j];
for(j=lp3;p[j];i++,j++)
line[i]=p[j];
line[i]='/0';
cout<<endl<<"After change : "<<line;
}
else
{
cout<<q<<" is not the substring of "<<line;
}
}
//===============================================================
void string::strempty()
{
int i=strlen(line);
if(i=0)
{
cout<<"The string is empty !";
}
else
{
cout<<"The string is not empty !";
}
}
//===============================================================
string string::operator = (string s1)
{
strcpy(line,s1.line);
return *this;
}
//===============================================================
string string::operator + (string s1)
{
strcat(line,s1.line);
return *this;
}
void string::operator <= (string s1)
{
int l=strlen(s1.line);
int m=strlen(line);
if(m<=l)
{
cout<<"less and equal";
}
else
{
cout<<"not less and equal";
}
}
//===============================================================
void string::operator != (string s1)
{
char n1[100];
strcpy(n1,s1.line);
int l;
l=strlen(line);
int m;
m=strlen(n1);
if(l!=m)
cout<<"judge not equal correct";
else
{
for(int i=0;i<l;i++)
{
if(line[i]==n1[i])
{
if(i==l-1)
cout<<"judge not equal error";
}
else
{
cout<<"judge not equal correct";
break;
}
}
}
}
//===============================================================
void string::operator ==(string s1)
{
char n1[100];
strcpy(n1,s1.line);
int m;
m=strlen(n1);
int l;
l=strlen(this->line);
if(l!=m)
{
cout<<"judge equal error";
}
else
{
for(int i=0;i<l;i++)
{
if(line[i]==n1[i])
{
if(i==l-1)
cout<<"judge equal correct";
}
else
{
cout<<"judge equal error";
break;
}
}
}
}
//===============================================================
char string::operator [](int pos)
{
int i=pos;
int l=strlen(line);
if(i>-1&&i<l)
{
cout<<"The word at "<<pos<<" is "<<line[i]<<endl;
return line[i];
}
else
{
cout<<"There is no word at "<<pos<<endl;
return 0;
}
}
//===============================================================
void main()
{
string s("The line is a line.");
cout<<"s.print():"<<endl;
s.print();
cout<<endl<<"s.turn():"<<endl;
s.turn();
cout<<endl<<"The length of the string is "<<s.strlength();
cout<<endl<<"s.substring(4,12):"<<endl;
s.substring(4,12);
cout<<endl<<"s.insert(5,abcdefgh):"<<endl;
s.insert(5,"abcdefgh");
cout<<endl<<"s.index(LINE):"<<endl;
s.index("LINE");
cout<<endl<<"s.index(xyz):"<<endl;
s.index("xyz");
cout<<endl<<"s.replace(abc,DingTao)"<<endl;
s.replace("abc","DingTao");
cout<<endl<<"s.replace(req,dakfj)"<<endl;
s.replace("req","dakfj");
cout<<endl<<"s.strempty():"<<endl;
s.strempty();
string s1("abc"),s2("def"),s3("ghi"),s4("abcdefg"),s5("2008");
cout<<endl<<"s1=abc/ts2=def/ts3=ghi/ts4=abcdefg/ts5=2008"<<endl;
cout<<"after s1=s1+s2 , s1=";
s1=s1+s2;
s1.print();
cout<<endl<<"s1<=s4"<<endl;
s1<=s4;
cout<<endl<<"s2==s4"<<endl;
s2==s4;
cout<<endl<<"s2!=s3"<<endl;
s2!=s3;
cout<<endl<<"s5[3]"<<endl;
s5[3];
}