let line;
while ((line = readline()) !== null) {
const counts = new Map();
for (const ch of line) {
counts.set(ch, (counts.get(ch) || 0) + 1);
}
let shouldPrint = false;
for (const count of counts.values()) {
if (count === 2) {
shouldPrint = true;
break;
}
}
if (shouldPrint) {
console.log(line);
}
}
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