44 lines
923 B
C
44 lines
923 B
C
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#include <stdio.h>
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#include <stdlib.h>
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#include <math.h>
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int dev(int a, int b, int p);
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int calcb(int a, int p);
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int main(int argc, char *argv[])
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{
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int p = 2000000;
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int a, b;
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int d1, d2; //dev of b, dev of b+1
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int cd, td; //current dev, min dev
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int tb, ta; //best a and b
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ta = tb = td = -1;
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for(a = 1; (b = calcb(a, p)) + 1 >= a; ++a){
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d1 = dev(a, b, p);
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d2 = dev(a, b + 1, p);
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cd = d1 > d2 ? d2 : d1;
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b += (d2 == cd);
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if(cd < td || td == -1){
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//smaller deviation
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td = cd;
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tb = b;
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ta = a;
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}
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}
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//printf("a = %d\nb = %d\ndev = %d\narea = %d\n", ta, tb, td, ta*tb);
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printf("%d\n", ta*tb);
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}
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//calculate b
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int calcb(int a, int p)
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{
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return (sqrt(1 + ((float) 16*p)/(a*a + a)) - 1)/2;
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}
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//eval deviation
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int dev(int a, int b, int p)
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{
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return abs(a*b*(a + 1)*(b + 1)/4 - p);
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}
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