[백준] JAVA 입력

reading any input at all

So scanner is slow. Use BufferedReader

BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

List given in 1 single line

10 2

StringTokenizer st = new StringTokenizer(br.readLine());
int n = Integer.parseInt(st.nextToken());
int m = Integer.parseInt(st.nextToken());

input that needs splitting for iter n

noj.am IU
acmicpc.net UAENA
startlink.io THEKINGOD
google.com ZEZE

        for (int i = 0; i < n; i++) {
            st = new StringTokenizer(br.readLine());
            String a = st.nextToken();
            String b = st.nextToken();
            map.put(a, b);
        }

input that doesnt need splitting for iter n

startlink.io
acmicpc.net
noj.am
mcc.hanyang.ac.kr

for (int i = 0; i < n; i++) {
            String a = br.readLine();
        }

For outputting with a new line in between

StringBuilder sb = new StringBuilder();
for (int i = 0; i < m; i++) {
            sb.append(map.get(a)).append("\n");
        }

        System.out.println(sb);