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

struct mytag {
	char tag[10];
};

bool equal(char a[10], char b[10]) {
	for (int i=0; i<10; i++) {
		if (a[i]!=b[i]) 
			return false;
	}
	return true;
}

int main () {
	int cases = 0;
	int numlines, index, linenum, i;
	bool error = false;
	bool starting;
	mytag tag;
	char thischar;
	scanf("%d%c",&numlines, &thischar);
	stack<mytag> tags;
	while (numlines) {
		while (!tags.empty()) tags.pop();
		error = false;
		cases++;
		cout << "Test Case " << cases << endl;
		linenum=1;
		while (linenum<=numlines) {
			scanf("%c",&thischar);
			if (thischar == '\n') {
				linenum++;
			}
			if (!error && thischar == '<') {
				for (i=0; i<10; i++) tag.tag[i]='\0';
				index=0;
				scanf("%c",&thischar);
				if (thischar == '\n') {
					linenum++;
				}
				if(thischar == '/'){
					scanf("%c",&thischar);
					if (thischar == '\n') {
						linenum++;
					}
					starting = false;
				}
				else starting = true;
				while (!error && thischar != '>') {
					if (thischar<'A' || thischar>'Z') {
						cout << "line " << linenum << ": bad character in tag name." << endl;
						error=true;
					}
					else {
						tag.tag[index]=thischar;
						index++;
						if (index>10) {
							cout << "line " << linenum << ": too many/few characters in tag name." << endl;
							error=true;
						}
					}
					scanf("%c",&thischar);
					if (thischar == '\n') {
						linenum++;
					}
				}
				if (!error && index==0) {
					cout << "line " << linenum << ": too many/few characters in tag name." << endl;
					error=true;
				}

				if (!error && starting)
					tags.push(tag);
				else {
					if (!error && tags.empty()){
						cout << "line " << linenum << ": no matching begin tag." << endl;
						error = true;

					}
					else if (!error && !equal(tags.top().tag,tag.tag)){
						cout << "line " << linenum << ": expected </" << tags.top().tag 
							<< ">" << endl;
						error = true;
					}
					else{
						if (!error) tags.pop();
					}
				}
			} //end if char is <
		} //end while
		if (!error && !tags.empty()){
			cout << "line " << linenum-1 << ": expected </" << tags.top().tag 
				<< ">" << endl;
			error = true;
		}
		if (!error)
			cout << "OK" << endl;
		scanf("%d%c",&numlines,&thischar);
	} // end for each case
	return 0;
}