#include<bits/stdc++.h>
int n,f[]={0,-1,-1,1,-1,1,2,-1,2,3,2,3,4,3,4,3,4,5,4,5,4,5,6,5,6,5,6,7,6,7,6,7,8,7,8,7,8,9,8,9,8,9,10,9,10,9,10,11,10,11,10,11,12,11,12,11,12,13,12,13,12,13,14,13,14,13,14,15,14,15,14,15,16,15,16,15,16,17,16,17,16,17,18,17,18,17,18,19,18,19,18,19,20,19,20,19,20,21,20,21,20,21,22,21,22,21,22,23,22,23,22,23,24,23,24,23,24,25,24,25,24,25,26,25,26,25,26,27,26,27,26,27,28,27,28,27,28,29,28,29,28,29,30,29,30,29,30,31,30,31,30,31,32,31,32,31,32,33,32,33,32,33,34,33,34,33,34,35,34,35,34,35,36,35,36,35,36,37,36,37,36,37,38,37,38,37,38,39,38,39,38,39,40,39,40,39,40,41,40,41,40,41,42,41,42,41,42,43,42,43,42,43,44,43,44,43,44,45,44,45,44,45,46,45,46,45,46,47,46,47,46,47,48,47,48,47,48,49,48,49,48,49,50,49,50,49,50,51,50,51,50,51,52,51,52,51,52,53,52,53,52,53,54,53,54,53,54,55,54,55,54,55,56,55,56,55,56,57,56,57,56,57,58,57,58,57,58,59,58,59,58,59,60,59,60,59,60,61,60,61,60,61,62,61,62,61,62,63,62,63,62,63,64,63,64,63,64,65,64,65,64,65,66,65,66,65,66,67,66,67,66,67,68,67,68,67,68,69,68,69,68,69,70,69,70,69,70,71,70,71,70,71,72,71,72,71,72,73,72,73,72,73,74,73,74,73,74,75,74,75,74,75,76,75,76,75,76,77,76,77,76,77,78,77,78,77,78,79,78,79,78,79,80,79,80,79,80,81,80,81,80,81,82,81,82,81,82,83,82,83,82,83,84,83,84,83,84,85,84,85,84,85,86,85,86,85,86,87,86,87,86,87,88,87,88,87,88,89,88,89,88,89,90,89,90,89,90,91,90,91,90,91,92,91,92,91,92,93,92,93,92,93,94,93,94,93,94,95,94,95,94,95,96,95,96,95,96,97,96,97,96,97,98,97,98,97,98,99,98,99,98,99,100,99,100,99,100,101,100,101,100,101,102,101,102,101,102,103,102,103,102,103,104,103,104,103,104,105,104,105,104,105,106,105,106,105,106,107,106,107,106,107,108,107,108,107,108,109,108,109,108,109,110,109,110,109,110,111,110,111,110,111,112,111,112,111,112,113,112,113,112,113,114,113,114,113,114,115,114,115,114,115,116,115,116,115,116,117,116,117,116,117,118,117,118,117,118,119,118,119,118,119,120,119,120,119,120,121,120,121,120,121,122,121,122,121,122,123,122,123,122,123,124,123,124,123,124,125,124,125,124,125,126,125,126,125,126,127,126,127,126,127,128,127,128,127,128,129,128,129,128,129,130,129,130,129,130,131,130,131,130,131,132,131,132,131,132,133,132,133,132,133,134,133,134,133,134,135,134,135,134,135,136,135,136,135,136,137,136,137,136,137,138,137,138,137,138,139,138,139,138,139,140,139,140,139,140,141,140,141,140,141,142,141,142,141,142,143,142,143,142,143,144,143,144,143,144,145,144,145,144,145,146,145,146,145,146,147,146,147,146,147,148,147,148,147,148,149,148,149,148,149,150,149,150,149,150,151,150,151,150,151,152,151,152,151,152,153,152,153,152,153,154,153,154,153,154,155,154,155,154,155,156,155,156,155,156,157,156,157,156,157,158,157,158,157,158,159,158,159,158,159,160,159,160,159,160,161,160,161,160,161,162,161,162,161,162,163,162,163,162,163,164,163,164,163,164,165,164,165,164,165,166,165,166,165,166,167,166,167,166,167,168,167,168,167,168,169,168,169,168,169,170,169,170,169,170,171,170,171,170,171,172,171,172,171,172,173,172,173,172,173,174,173,174,173,174,175,174,175,174,175,176,175,176,175,176,177,176,177,176,177,178,177,178,177,178,179,178,179,178,179,180,179,180,179,180,181,180,181,180,181,182,181,182,181,182,183,182,183,182,183,184,183,184,183,184,185,184,185,184,185,186,185,186,185,186,187,186,187,186,187,188,187,188,187,188,189,188,189,188,189,190,189,190,189,190,191,190,191,190,191,192,191,192,191,192,193,192,193,192,193,194,193,194,193,194,195,194,195,194,195,196,195,196,195,196,197,196,197,196,197,198,197,198,197,198,199,198,199,198,199,200,199,200,199,200,201,200,201,200,201,202,201,202,201,202,203,202,203,202,203,204,203,204,203,204,205,204,205,204,205,206,205,206,205,206,207,206,207,206,207,208,207,208,207,208,209,208,209,208,209,210,209,210,209,210,211,210,211,210,211,212,211,212,211,212,213,212,213,212,213,214,213,214,213,214,215,214,215,214,215,216,215,216,215,216,217,216,217,216,217,218,217,218,217,218,219,218,219,218,219,220,219,220,219,220,221,220,221,220,221,222,221,222,221,222,223,222,223,222,223,224,223,224,223,224,225,224,225,224,225,226,225,226,225,226,227,226,227,226,227,228,227,228,227,228,229,228,229,228,229,230,229,230,229,230,231,230,231,230,231,232,231,232,231,232,233,232,233,232,233,234,233,234,233,234,235,234,235,234,235,236,235,236,235,236,237,236,237,236,237,238,237,238,237,238,239,238,239,238,239,240,239,240,239,240,241,240,241,240,241,242,241,242,241,242,243,242,243,242,243,244,243,244,243,244,245,244,245,244,245,246,245,246,245,246,247,246,247,246,247,248,247,248,247,248,249,248,249,248,249,250,249,250,249,250,251,250,251,250,251,252,251,252,251,252,253,252,253,252,253,254,253,254,253,254,255,254,255,254,255,256,255,256,255,256,257,256,257,256,257,258,257,258,257,258,259,258,259,258,259,260,259,260,259,260,261,260,261,260,261,262,261,262,261,262,263,262,263,262,263,264,263,264,263,264,265,264,265,264,265,266,265,266,265,266,267,266,267,266,267,268,267,268,267,268,269,268,269,268,269,270,269,270,269,270,271,270,271,270,271,272,271,272,271,272,273,272,273,272,273,274,273,274,273,274,275,274,275,274,275,276,275,276,275,276,277,276,277,276,277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signed main(){ std::cin>>n,std::cout<<f[n]; }