Substring primes: Difference between revisions
→{{header|ALGOL W}}
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2 3 5 7 23 37 53 73 373
Found 9 substring primes
</pre>
=={{header|AWK}}==
<lang AWK>
# syntax: GAWK -f SUBSTRING_PRIMES.AWK
# converted from FreeBASIC
BEGIN {
start = 1
stop = 500
for (i=start; i<=stop; i++) {
if (is_substring_prime(i)) {
printf("%d ",i)
count++
}
}
printf("\nSubString Primes %d-%d: %d\n",start,stop,count)
exit(0)
}
function is_prime(x, i) {
if (x <= 1) {
return(0)
}
for (i=2; i<=int(sqrt(x)); i++) {
if (x % i == 0) {
return(0)
}
}
return(1)
}
function is_substring_prime(n) {
if (!is_prime(i)) { return(0) }
if (n < 10) { return(1) }
if (!is_prime(n%100)) { return(0) }
if (!is_prime(n%10)) { return(0) }
if (!is_prime(int(n/10))) { return(0) }
if (n < 100) { return(1) }
if (!is_prime(int(n/100))) { return(0) }
if (!is_prime(int((n%100)/10))) { return(0) }
return(1)
}
</lang>
{{out}}
<pre>
2 3 5 7 23 37 53 73 373
SubString Primes 1-500: 9
</pre>
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