DNA complementary sequence conversion C++

DNA is Deoxyribonucleic acid which encoding the genetic instructions including cell function and development of organisms.

DNA consist of 2 strands and each sequence is complementary. So, we can get a complementary sequence if we have a template sequence.

A - T (T - A)

G - C (C - G)

This is simple c++ programming code.

Input comes from user's input parameter in command.

If the program name is reverse, then ./reverse ACGT

The result will be like that.

./reverse ACGT

Input sequence: ACGT

Output sequence: TGCA

#include<iostream>

#include<string.h>

#include<stdlib.h>

using namespace std;

string convert(string str);

int main(int argc, char* argv[]){

    string str(argv[1]);

    string revcomp = convert(str);

    cout<<"Input  sequence: "<<str<<endl;

    cout<<"Output sequence: "<<revcomp<<endl;

}

string convert(string str){

    for(int i=0;i<str.length();i++){

        switch( str[i] ){

            case 'A':

                str[i] = 'T';

                break;

            case 'C':

                str[i] = 'G';

                break;

            case 'G':

                str[i] = 'C';

                break;

            case 'T':

                str[i] = 'A';

                break;

            default:

                cout<<"Argument error."<<endl;

                exit(-1);

        }

    }

    return str;

}

This is result figure.