用结构体做的

using namespace std;
struct info{
	string dc;
	int cs;
}; 
info a[200];
int main() {
	int n;
	cin >> n;
	for(int i = 0; i < n; i ++){
		cin >> a[i].dc;
		a[i].cs = 0;
		int k = a[i].dc.size();
		string s = a[i].dc;
		for(int j = 0; j < k; j ++){
			//string s = a[i].dc;
			if(s[j] >= 'A' && s[j] <= 'Z'){
				s[j] = s[j] + 32;
			}
		}
		a[i].dc = s;	
	}
	//int idx = 0;
	for(int i = 0; i < n; i ++){
		for(int j =0; j < n; j ++){
			if(i != j){
				if(a[i].dc == a[j].dc){
					a[i].cs ++;
				}
			}
		}
	}
	int ma = -1;
	string q ="";
	for(int i = 0; i < n; i ++){
		if(a[i].cs > ma){
			ma = a[i].cs;
			q = a[i].dc;
		}
	}	
	cout << q;
    return 0;
}  ```