DNA序列

#include<iostream>
#include<string>
using namespace std;

int main(){
string dna,temp;
int count = 0,max = 0,n;
cin >> dna>>n;
if (n > dna.size())
return 0;
else{
for (int i = 0; i <= dna.size() - n; i++){
for (int j = 0; j < n; j++){ //计算以i为起点长度为n的子串中，C和G的字符个数。
if (dna.substr(i, n)[j] == 'C' || dna.substr(i, n)[j] == 'G')
count++;
}
if (count>max){
max = count;
temp = dna.substr(i, n);
}
count = 0;
}
}
cout << temp << endl;
system("pause");
return 0;
}