57 lines
1.2 KiB
C++
57 lines
1.2 KiB
C++
/** A unit fraction contains 1 in the numerator. The decimal representation of the unit fractions with denominators 2 to 10 are given:
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1/2 = 0.5
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1/3 = 0.(3)
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1/4 = 0.25
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1/5 = 0.2
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1/6 = 0.1(6)
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1/7 = 0.(142857)
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1/8 = 0.125
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1/9 = 0.(1)
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1/10 = 0.1
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Where 0.1(6) means 0.166666..., and has a 1-digit recurring cycle. It can be seen that 1/7 has a 6-digit recurring cycle.
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Find the value of d < 1000 for which 1/d contains the longest recurring cycle in its decimal fraction part. */
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#include "0.hpp"
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const int _max = 10000;
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int cycle(int num)
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{
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int mod[_max] = {0};
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int temp = 10;
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int count = 0;
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int flag = 1;
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do {
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if(temp == 0) break;
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if(temp < num) temp *= 10;
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//cout << temp / num;
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temp %= num;
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mod[count] = temp;
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for(int i = 0; i <= count - 1; i++)
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if(temp == mod[i]) {
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flag = 0;
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count -= i;
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count--;
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}
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count++;
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} while(flag);
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//cout << '\t' << count << endl;
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return count;
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}
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int main()
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{
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int max[2] = {0, 0};
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for(int i = 2; i <= _max; i++) {
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//cout << i << '\t';
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int temp = cycle(i);
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if(temp > max[1]) {
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max[0] = i;
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max[1] = temp;
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}
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}
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cout << max[0] << '\t' << max[1] << endl;
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return 0;
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}
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