CODEWITHSUNDEEP
c++stringc++11
GameX
GameX

Reputation: 67

Lexicographical string comparison using loops

I want to lexicographically compare two strings of equal length, containing Latin letters. Uppercase and lowercase letters are considered same.

Here is my code:

string in1,in2;
    getline(cin,in1);
    getline(cin,in2);
    int l=in1.length();

    for(int i=0;i<l;++i){
        in1[i]=tolower(in1[i]);
        in2[i]=tolower(in2[i]);
    }

    int sum1=0;
    int sum2=0;
    for(int i=0;i<l;++i){
        sum1=sum1 + int(in1[i]);
        sum2=sum2 + int(in2[i]);
    }
    if(sum1==sum2)
        cout<<"0"<<endl;
    if(sum1<sum2)
        cout<<"-1"<<endl;
    if(sum1>sum2)
        cout<<"1"<<endl;

However, this gives errors on certain test conditions.

What is wrong here?

Upvotes: 0

Views: 325

Answers (4)

Ramkumar lodhi
Ramkumar lodhi

Reputation: 131

You can use compare function

int x = in1.compare(in2);
if(x == 0)
     cout<<"Both are Equal";
else if (x > 0) 
    cout << in1 << " is greater than "<< in2 << endl; 
else
    cout << in2 << " is greater than "<< in1 << endl;

Upvotes: 1

Adrian Mole
Adrian Mole

Reputation: 51864

You can surely use the operators provided by the standard library for std::string types:

operator==
operator!=
operator<             lexicographically compares two strings
operator>             (function template)
operator<=
operator>=

For more information, see here.

Upvotes: 1

OrenIshShalom
OrenIshShalom

Reputation: 7152

You can use strcmp with the std::string C string extractor c_str(). Here is a complete working solution that does it:

#include <iostream>
#include <string>
#include <string.h>

int main(int argc, char **argv)
{
    std::string s1("aabad");
    std::string s2("abaaaaaaa");
    if (strcmp(s1.c_str(),s2.c_str()) <  0) std::cout << "s1 <  s2\n";
    if (strcmp(s1.c_str(),s2.c_str()) >  0) std::cout << "s2 <  s1\n";
    if (strcmp(s1.c_str(),s2.c_str()) == 0) std::cout << "s1 == s2\n";
    return 0;
}

Upvotes: 1

Che Huu
Che Huu

Reputation: 163

I think it wrong because it doesn't consider the order of characters. For example "ab" and "ba" will get the same sum.

Upvotes: 1

Related Questions