// Rain Dreamer MODEL // iSea @ 2014-08-31 19:35 // Comment - #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; // Self Template Code BGEIN #define sz(x) ((int)((x).size())) #define out(x) printf(#x" %d\n", x) #define rep(i,n) for (int i = 0; i < (n); ++i) #define repf(i,a,b) for (int i = (a); i <= (b); ++i) #define repd(i,a,b) for (int i = (a); i >= (b); --i) #define repcase int t, Case = 1; for (scanf ("%d", &t); t; --t) #define repeach(i,x) for (__typeof((x).begin()) i = (x).begin(); i != (x).end(); ++i) typedef long long int64; typedef pair pii; int sgn(double x) { return (x > 1e-8) - (x < -1e-8); } int count_bit(int x) { return x == 0? 0 : count_bit(x >> 1) + (x & 1); } template inline void ckmin(T &a, const T b) { if (b < a) a = b; } template inline void ckmax(T &a, const T b) { if (b > a) a = b; } // Self Template Code END double a[1010] = { 0, 14.39272672, 15.08587365, 15.49133868, 15.77902071, 16.00216424, 16.18448578, 16.33863644, 16.47216783, 16.58995086, 16.69531137, 16.79062154, 16.87763291, 16.95767562, 17.03178359, 17.10077646, 17.16531498, 17.22593960, 17.28309801, 17.33716523, 17.38845852, 17.43724868, 17.48376870, 17.52822046, 17.57078007, 17.61160207, 17.65082278, 17.68856311, 17.72493075, 17.76002207, 17.79392362, 17.82671344, 17.85846214, 17.88923380, 17.91908676, 17.94807430, 17.97624518, 18.00364415, 18.03031240, 18.05628788, 18.08160569, 18.10629830, 18.13039585, 18.15392635, 18.17691587, 18.19938872, 18.22136763, 18.24287384, 18.26392724, 18.28454653, 18.30474924, 18.32455187, 18.34396995, 18.36301815, 18.38171028, 18.40005942, 18.41807792, 18.43577750, 18.45316924, 18.47026368, 18.48707079, 18.50360010, 18.51986062, 18.53586096, 18.55160931, 18.56711350, 18.58238097, 18.59741885, 18.61223394, 18.62683273, 18.64122147, 18.65540611, 18.66939235, 18.68318567, 18.69679132, 18.71021434, 18.72345957, 18.73653165, 18.74943506, 18.76217408, 18.77475286, 18.78717538, 18.79944548, 18.81156684, 18.82354303, 18.83537749, 18.84707352, 18.85863435, 18.87006304, 18.88136260, 18.89253590, 18.90358573, 18.91451481, 18.92532572, 18.93602101, 18.94660312, 18.95707442, 18.96743721, 18.97769371, 18.98784608, 18.99789641, 19.00784674, 19.01769904, 19.02745522, 19.03711713, 19.04668658, 19.05616532, 19.06555506, 19.07485745, 19.08407411, 19.09320659, 19.10225643, 19.11122510, 19.12011405, 19.12892468, 19.13765836, 19.14631642, 19.15490016, 19.16341085, 19.17184972, 19.18021797, 19.18851677, 19.19674727, 19.20491058, 19.21300779, 19.22103996, 19.22900813, 19.23691331, 19.24475649, 19.25253863, 19.26026068, 19.26792355, 19.27552815, 19.28307535, 19.29056603, 19.29800101, 19.30538111, 19.31270715, 19.31997991, 19.32720016, 19.33436865, 19.34148612, 19.34855328, 19.35557086, 19.36253953, 19.36945997, 19.37633285, 19.38315881, 19.38993850, 19.39667253, 19.40336152, 19.41000606, 19.41660675, 19.42316415, 19.42967883, 19.43615134, 19.44258223, 19.44897203, 19.45532126, 19.46163043, 19.46790004, 19.47413059, 19.48032256, 19.48647643, 19.49259265, 19.49867170, 19.50471401, 19.51072004, 19.51669021, 19.52262494, 19.52852466, 19.53438978, 19.54022070, 19.54601782, 19.55178152, 19.55751220, 19.56321022, 19.56887596, 19.57450978, 19.58011203, 19.58568308, 19.59122326, 19.59673291, 19.60221238, 19.60766198, 19.61308205, 19.61847290, 19.62383484, 19.62916819, 19.63447324, 19.63975030, 19.64499965, 19.65022160, 19.65541641, 19.66058438, 19.66572578, 19.67084088, 19.67592995, 19.68099326, 19.68603105, 19.69104359, 19.69603113, 19.70099392, 19.70593220, 19.71084622, 19.71573620, 19.72060239, 19.72544502, 19.73026430, 19.73506048, 19.73983376, 19.74458436, 19.74931250, 19.75401839, 19.75870224, 19.76336425, 19.76800463, 19.77262358, 19.77722129, 19.78179795, 19.78635377, 19.79088893, 19.79540361, 19.79989800, 19.80437228, 19.80882663, 19.81326122, 19.81767624, 19.82207185, 19.82644823, 19.83080553, 19.83514394, 19.83946360, 19.84376468, 19.84804734, 19.85231174, 19.85655803, 19.86078637, 19.86499690, 19.86918978, 19.87336515, 19.87752316, 19.88166395, 19.88578767, 19.88989445, 19.89398444, 19.89805776, 19.90211456, 19.90615497, 19.91017912, 19.91418714, 19.91817916, 19.92215531, 19.92611571, 19.93006049, 19.93398977, 19.93790367, 19.94180231, 19.94568581, 19.94955429, 19.95340786, 19.95724663, 19.96107073, 19.96488026, 19.96867533, 19.97245605, 19.97622253, 19.97997488, 19.98371321, 19.98743760, 19.99114818, 19.99484505, 19.99852829, 20.00219802, 20.00585433, 20.00949732, 20.01312709, 20.01674373, 20.02034734, 20.02393801, 20.02751583, 20.03108089, 20.03463330, 20.03817312, 20.04170046, 20.04521540, 20.04871804, 20.05220844, 20.05568670, 20.05915291, 20.06260715, 20.06604949, 20.06948003, 20.07289883, 20.07630599, 20.07970158, 20.08308568, 20.08645836, 20.08981971, 20.09316980, 20.09650870, 20.09983649, 20.10315324, 20.10645903, 20.10975393, 20.11303800, 20.11631133, 20.11957397, 20.12282601, 20.12606750, 20.12929852, 20.13251914, 20.13572941, 20.13892941, 20.14211921, 20.14529886, 20.14846844, 20.15162800, 20.15477761, 20.15791733, 20.16104722, 20.16416735, 20.16727777, 20.17037855, 20.17346974, 20.17655141, 20.17962361, 20.18268640, 20.18573983, 20.18878398, 20.19181888, 20.19484460, 20.19786119, 20.20086871, 20.20386722, 20.20685676, 20.20983738, 20.21280915, 20.21577212, 20.21872633, 20.22167184, 20.22460870, 20.22753696, 20.23045667, 20.23336788, 20.23627064, 20.23916500, 20.24205100, 20.24492870, 20.24779815, 20.25065938, 20.25351245, 20.25635740, 20.25919428, 20.26202314, 20.26484401, 20.26765696, 20.27046201, 20.27325921, 20.27604861, 20.27883026, 20.28160418, 20.28437044, 20.28712906, 20.28988009, 20.29262358, 20.29535956, 20.29808807, 20.30080916, 20.30352287, 20.30622923, 20.30892829, 20.31162008, 20.31430464, 20.31698202, 20.31965225, 20.32231537, 20.32497141, 20.32762042, 20.33026243, 20.33289748, 20.33552560, 20.33814683, 20.34076121, 20.34336878, 20.34596956, 20.34856359, 20.35115092, 20.35373156, 20.35630557, 20.35887296, 20.36143378, 20.36398806, 20.36653584, 20.36907713, 20.37161199, 20.37414044, 20.37666250, 20.37917823, 20.38168764, 20.38419077, 20.38668765, 20.38917831, 20.39166279, 20.39414110, 20.39661329, 20.39907938, 20.40153941, 20.40399340, 20.40644138, 20.40888338, 20.41131944, 20.41374957, 20.41617382, 20.41859220, 20.42100474, 20.42341148, 20.42581245, 20.42820766, 20.43059714, 20.43298094, 20.43535906, 20.43773154, 20.44009840, 20.44245968, 20.44481539, 20.44716557, 20.44951024, 20.45184942, 20.45418314, 20.45651143, 20.45883431, 20.46115181, 20.46346395, 20.46577076, 20.46807226, 20.47036847, 20.47265942, 20.47494513, 20.47722564, 20.47950095, 20.48177110, 20.48403611, 20.48629599, 20.48855079, 20.49080051, 20.49304518, 20.49528482, 20.49751946, 20.49974911, 20.50197381, 20.50419356, 20.50640840, 20.50861835, 20.51082342, 20.51302364, 20.51521903, 20.51740961, 20.51959541, 20.52177643, 20.52395271, 20.52612427, 20.52829112, 20.53045328, 20.53261078, 20.53476363, 20.53691186, 20.53905548, 20.54119452, 20.54332899, 20.54545892, 20.54758432, 20.54970521, 20.55182161, 20.55393355, 20.55604103, 20.55814408, 20.56024271, 20.56233696, 20.56442682, 20.56651233, 20.56859349, 20.57067034, 20.57274288, 20.57481113, 20.57687511, 20.57893485, 20.58099035, 20.58304163, 20.58508871, 20.58713161, 20.58917035, 20.59120494, 20.59323540, 20.59526174, 20.59728399, 20.59930215, 20.60131625, 20.60332630, 20.60533232, 20.60733432, 20.60933232, 20.61132634, 20.61331639, 20.61530249, 20.61728465, 20.61926289, 20.62123723, 20.62320767, 20.62517424, 20.62713695, 20.62909581, 20.63105085, 20.63300207, 20.63494949, 20.63689312, 20.63883299, 20.64076910, 20.64270147, 20.64463011, 20.64655504, 20.64847627, 20.65039381, 20.65230769, 20.65421791, 20.65612449, 20.65802744, 20.65992677, 20.66182251, 20.66371466, 20.66560323, 20.66748825, 20.66936971, 20.67124765, 20.67312206, 20.67499297, 20.67686038, 20.67872432, 20.68058478, 20.68244179, 20.68429536, 20.68614550, 20.68799223, 20.68983554, 20.69167547, 20.69351202, 20.69534520, 20.69717503, 20.69900151, 20.70082467, 20.70264450, 20.70446103, 20.70627427, 20.70808423, 20.70989091, 20.71169434, 20.71349452, 20.71529146, 20.71708519, 20.71887570, 20.72066301, 20.72244713, 20.72422807, 20.72600585, 20.72778048, 20.72955195, 20.73132030, 20.73308553, 20.73484764, 20.73660666, 20.73836258, 20.74011543, 20.74186522, 20.74361194, 20.74535562, 20.74709626, 20.74883388, 20.75056849, 20.75230009, 20.75402870, 20.75575433, 20.75747698, 20.75919667, 20.76091341, 20.76262721, 20.76433807, 20.76604601, 20.76775104, 20.76945317, 20.77115241, 20.77284876, 20.77454224, 20.77623286, 20.77792062, 20.77960554, 20.78128763, 20.78296689, 20.78464334, 20.78631698, 20.78798782, 20.78965588, 20.79132116, 20.79298367, 20.79464342, 20.79630042, 20.79795468, 20.79960621, 20.80125501, 20.80290111, 20.80454449, 20.80618518, 20.80782318, 20.80945851, 20.81109116, 20.81272115, 20.81434849, 20.81597319, 20.81759525, 20.81921468, 20.82083150, 20.82244570, 20.82405731, 20.82566632, 20.82727274, 20.82887659, 20.83047787, 20.83207659, 20.83367276, 20.83526639, 20.83685748, 20.83844604, 20.84003209, 20.84161562, 20.84319665, 20.84477518, 20.84635122, 20.84792479, 20.84949588, 20.85106451, 20.85263068, 20.85419440, 20.85575568, 20.85731453, 20.85887095, 20.86042495, 20.86197654, 20.86352573, 20.86507252, 20.86661692, 20.86815894, 20.86969859, 20.87123587, 20.87277079, 20.87430335, 20.87583358, 20.87736146, 20.87888701, 20.88041024, 20.88193115, 20.88344976, 20.88496606, 20.88648006, 20.88799178, 20.88950121, 20.89100837, 20.89251326, 20.89401589, 20.89551627, 20.89701440, 20.89851028, 20.90000394, 20.90149536, 20.90298456, 20.90447155, 20.90595633, 20.90743891, 20.90891930, 20.91039750, 20.91187351, 20.91334735, 20.91481902, 20.91628853, 20.91775588, 20.91922108, 20.92068414, 20.92214506, 20.92360385, 20.92506052, 20.92651506, 20.92796749, 20.92941782, 20.93086605, 20.93231218, 20.93375622, 20.93519818, 20.93663807, 20.93807588, 20.93951163, 20.94094533, 20.94237697, 20.94380656, 20.94523411, 20.94665963, 20.94808312, 20.94950458, 20.95092403, 20.95234146, 20.95375689, 20.95517032, 20.95658175, 20.95799119, 20.95939865, 20.96080414, 20.96220764, 20.96360919, 20.96500877, 20.96640639, 20.96780206, 20.96919579, 20.97058758, 20.97197744, 20.97336536, 20.97475136, 20.97613545, 20.97751762, 20.97889788, 20.98027624, 20.98165270, 20.98302727, 20.98439996, 20.98577076, 20.98713968, 20.98850674, 20.98987193, 20.99123525, 20.99259672, 20.99395634, 20.99531412, 20.99667005, 20.99802414, 20.99937641, 21.00072685, 21.00207547, 21.00342227, 21.00476726, 21.00611044, 21.00745182, 21.00879141, 21.01012920, 21.01146521, 21.01279943, 21.01413188, 21.01546255, 21.01679145, 21.01811859, 21.01944397, 21.02076760, 21.02208948, 21.02340961, 21.02472800, 21.02604466, 21.02735958, 21.02867278, 21.02998425, 21.03129401, 21.03260206, 21.03390839, 21.03521302, 21.03651596, 21.03781719, 21.03911674, 21.04041460, 21.04171077, 21.04300527, 21.04429810, 21.04558925, 21.04687874, 21.04816657, 21.04945275, 21.05073727, 21.05202014, 21.05330137, 21.05458096, 21.05585892, 21.05713524, 21.05840994, 21.05968302, 21.06095447, 21.06222431, 21.06349254, 21.06475917, 21.06602419, 21.06728762, 21.06854945, 21.06980968, 21.07106834, 21.07232541, 21.07358090, 21.07483482, 21.07608717, 21.07733795, 21.07858717, 21.07983483, 21.08108094, 21.08232549, 21.08356850, 21.08480997, 21.08604989, 21.08728828, 21.08852514, 21.08976047, 21.09099428, 21.09222656, 21.09345733, 21.09468659, 21.09591434, 21.09714058, 21.09836532, 21.09958856, 21.10081031, 21.10203056, 21.10324933, 21.10446662, 21.10568242, 21.10689675, 21.10810961, 21.10932100, 21.11053092, 21.11173938, 21.11294638, 21.11415192, 21.11535602, 21.11655866, 21.11775987, 21.11895963, 21.12015795, 21.12135484, 21.12255029, 21.12374432, 21.12493693, 21.12612812, 21.12731788, 21.12850624, 21.12969318, 21.13087872, 21.13206285, 21.13324558, 21.13442692, 21.13560686, 21.13678541, 21.13796257, 21.13913835, 21.14031275, 21.14148577, 21.14265742, 21.14382769, 21.14499660, 21.14616414, 21.14733032, 21.14849515, 21.14965861, 21.15082073, 21.15198149, 21.15314091, 21.15429899, 21.15545573, 21.15661113, 21.15776520, 21.15891794, 21.16006935, 21.16121944, 21.16236820, 21.16351565, 21.16466178, 21.16580660, 21.16695011, 21.16809231, 21.16923322, 21.17037282, 21.17151112, 21.17264813, 21.17378385, 21.17491828, 21.17605142, 21.17718329, 21.17831387, 21.17944317, 21.18057121, 21.18169797, 21.18282346, 21.18394769, 21.18507065, 21.18619236, 21.18731280, 21.18843200, 21.18954994, 21.19066664, 21.19178209, 21.19289629, 21.19400926, 21.19512099, 21.19623148, 21.19734074, 21.19844878, 21.19955558, 21.20066117, 21.20176553, 21.20286867, 21.20397060, 21.20507132, 21.20617082, 21.20726912, 21.20836621, 21.20946210, 21.21055680, 21.21165029, 21.21274259, 21.21383370, 21.21492361, 21.21601235, 21.21709989, 21.21818626, 21.21927145, 21.22035546, 21.22143830, 21.22251996, 21.22360046, 21.22467979, 21.22575796, 21.22683496, 21.22791081, 21.22898550, 21.23005904, 21.23113142, 21.23220266, 21.23327275, 21.23434170, 21.23540951, 21.23647617, 21.23754170, 21.23860610, 21.23966936, 21.24073150, 21.24179251, 21.24285239, 21.24391115, 21.24496879, 21.24602532, 21.24708073, 21.24813502, 21.24918821, 21.25024029, 21.25129126, 21.25234113, 21.25338989, 21.25443756, 21.25548414, 21.25652961, 21.25757400, 21.25861730, 21.25965951, 21.26070063, 21.26174067, 21.26277964, 21.26381752, 21.26485432, 21.26589006, 21.26692472, 21.26795831, 21.26899084, 21.27002230, 21.27105269, 21.27208203, 21.27311031, 21.27413753, 21.27516369, 21.27618881, 21.27721288, 21.27823589, 21.27925787, 21.28027880, 21.28129868, 21.28231753, 21.28333534, 21.28435212, 21.28536786, 21.28638258, 21.28739626, 21.28840892, 21.28942056, 21.29043117, 21.29144076, 21.29244933, 21.29345689, 21.29446343, 21.29546896, 21.29647348, 21.29747699, 21.29847950, 21.29948100, 21.30048150 }; int main() { int n; while ( scanf ("%d", &n) != EOF ) { int t = n / 1000000; double ret = a[t]; repf (i, t * 1000000 + 1, n) { ret += 1.0 / i; } printf ("%.4lf\n", ret); } return 0; }