public import std;

DList!string scan_buffer;
DList!char char_buffer;
static this() {
    scan_buffer = DList!(string)();
    char_buffer = DList!(char)();
}

void cin()() {

}

void cin(T, A...)(ref T a, ref A tail) {
    import std.traits : isArray;

    static if (typeof(a).stringof == "string") {
        if (!char_buffer.empty) {
            a = char_buffer.array.map!(x => x.to!string).join();
            char_buffer.clear();
        } else {
            while (scan_buffer.empty) {
                foreach (t; readln.split) {
                    if (t.length == 0) {
                        continue;
                    }
                    scan_buffer.insert(t);
                }
            }
            auto token = scan_buffer.front;
            scan_buffer.removeFront();
            a = token;
        }
    } else static if (typeof(a).stringof == "char") {
        if (!char_buffer.empty) {
            a = char_buffer.front();
            char_buffer.removeFront();
        } else {
            while (scan_buffer.empty) {
                foreach (t; readln.split) {
                    if (t.length == 0) {
                        continue;
                    }
                    scan_buffer.insert(t);
                }
            }
            auto token = scan_buffer.front;
            scan_buffer.removeFront();
            a = token[0];
            if (token.length > 1) {
                foreach (c; token[1 .. $]) {
                    char_buffer.insertBack(c);
                }
            }
        }
    } else static if (typeof(a).stringof == "char[]") {
        if (a.length == 0) {
            string token;
            cin(token);
            foreach (c; token) {
                a ~= c;
            }
        } else {
            foreach (ref v; a) {
                cin(v);
            }
        }
    } else static if (isArray!(typeof(a))) {
        foreach (ref v; a) {
            cin(v);
        }
    } else static if (isTuple!(typeof(a))) {
        foreach (i, _; a) {
            cin(a[i]);
        }
    } else {
        if (!char_buffer.empty) {
            writeln(char_buffer.array.map!(x => x.to!string));
            a = char_buffer.array.map!(x => x.to!string).join().to!T;
            char_buffer.clear();
        } else {
            while (scan_buffer.empty) {
                foreach (t; readln.split) {
                    if (t.length == 0) {
                        continue;
                    }
                    scan_buffer.insert(t);
                }
            }
            auto token = scan_buffer.front;
            scan_buffer.removeFront();
            a = token.to!T;
        }
    }
    cin(tail);
}

bool chmin(T)(ref T a, T b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}

bool chmax(T)(ref T a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}

alias PQueue(T = long, alias less = "a<b") = BinaryHeap!(Array!T, less);

void main() {
    long L, R, C;
    cin(L, R, C);
    long ans = 1000;
    foreach (i; L .. min(L + 1005, R + 1)) {
        ans.chmin((1000 - ((i * C) % 1000)) % 1000);
    }
    ans.writeln;
}