10 lines
198 B
C
10 lines
198 B
C
int is_prime(unsigned int n)
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{
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unsigned int p;
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if (!(n & 1) || n < 2 ) return n == 2;
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/* comparing p*p <= n can overflow */
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for (p = 3; p <= n/p; p += 2)
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if (!(n % p)) return 0;
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return 1;
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}
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