74 lines
1.0 KiB
C
74 lines
1.0 KiB
C
#include <stdio.h>
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#include <stdlib.h>
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#include <math.h>
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#include <time.h>
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#include "projecteuler.h"
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int is_tr_prime(int n);
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int main(int argc, char **argv)
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{
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int i = 0, n = 1, sum = 0;
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double elapsed;
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struct timespec start, end;
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clock_gettime(CLOCK_MONOTONIC, &start);
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while(i < 11)
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{
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if(is_tr_prime(n))
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{
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sum += n;
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i++;
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}
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n++;
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}
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clock_gettime(CLOCK_MONOTONIC, &end);
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elapsed = (end.tv_sec - start.tv_sec) + (double)(end.tv_nsec - start.tv_nsec) / 1000000000;
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printf("Project Euler, Problem 37\n");
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printf("Answer: %d\n", sum);
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printf("Elapsed time: %.9lf seconds\n", elapsed);
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return 0;
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}
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int is_tr_prime(int n)
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{
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int i, tmp;
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if(n < 11 || !is_prime(n))
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{
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return 0;
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}
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tmp = n / 10;
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while(tmp > 0)
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{
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if(!is_prime(tmp))
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{
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return 0;
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}
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tmp /= 10;
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}
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i = 10;
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tmp = n % i;
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while(tmp != n)
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{
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if(!is_prime(tmp))
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{
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return 0;
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}
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i *= 10;
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tmp = n % i;
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}
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return 1;
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}
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