题解 | #DNA序列#

#include <bits/stdc++.h>
using namespace std;

int main() {
    string str;
    getline(cin, str);
    int n;
    cin >> n;
    int count[1000] = {0};
    int maxc = 0;
    for (int i = 0; i <= str.length() - n; i++) {
        for (int j = i; j < i + n; j++) {
            if (str[j] == 'C' || str[j] == 'G') {
                count[i]++;
            }
        }
        maxc = max(count[i], maxc);
    }
    for (int i = 0; i <= str.length() - n; i++) {
        if (count[i] == maxc) {
            cout << str.substr(i, n) << endl;
            break;
        }
    }
}