#include #include #include #include int main(int argc, char **argv) { double elapsed; struct timespec start, end; mpz_t fact, r, sum; clock_gettime(CLOCK_MONOTONIC, &start); mpz_inits(fact, r, sum, NULL); mpz_fac_ui(fact, 100); mpz_set_ui(sum, 0); while(mpz_cmp_ui(fact, 0)) { mpz_tdiv_qr_ui(fact, r, fact, 10); mpz_add(sum, sum, r); } clock_gettime(CLOCK_MONOTONIC, &end); elapsed=(end.tv_sec-start.tv_sec)+(double)(end.tv_nsec-start.tv_nsec)/1000000000; printf("Project Euler, Problem 20\n"); gmp_printf("Answer: %Zd\n", sum); printf("Elapsed time: %.9lf seconds\n", elapsed); mpz_clears(fact, r, sum, NULL); return 0; }