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import org.junit.Test;
import static org.junit.Assert.*;

public class Sample180 {
    public int modular(int n, int low, int high) {
        int count = (high - low + 1);
        int res = n % count;
        while (res < 0) {
            res += count;
        }
        return res + low;
    }

    @Test
    public void testModular() {
        assertEquals(100, modular(0, 100, 200));
        assertEquals(150, modular(50, 100, 200));
        assertEquals(200, modular(100, 100, 200));

        assertEquals(100, modular(101, 100, 200));
        assertEquals(200, modular(-1, 100, 200));
        assertEquals(-4, modular(1, -5, 200));
        assertEquals(-5, modular(-500, -5, -1));
    }
}