Find adjacent primes which differ by a square integer: Difference between revisions
Find adjacent primes which differ by a square integer (view source)
Revision as of 13:22, 21 November 2021
, 2 years agoadd C
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<br>Find adjacents primes which difference '''(>36)''' is square integer under '''1,000,000'''
<br><br>
=={{header|C}}==
<lang>#include<stdio.h>
#include<stdlib.h>
int isprime( int p ) {
int i;
if(p==2) return 1;
if(!(p%2)) return 0;
for(i=3; i*i<=p; i+=2) {
if(!(p%i)) return 0;
}
return 1;
}
int nextprime( int p ) {
int i=0;
if(p==0) return 2;
if(p<3) return p+1;
while(!isprime(++i + p));
return i+p;
}
int issquare( int p ) {
int i;
for(i=0;i*i<p;i++);
return i*i==p;
}
int main(void) {
int i=3, j=2;
for(i=3;j<=1000000;i=j) {
j=nextprime(i);
if(j-i>36&&issquare(j-i)) printf( "%d %d %d\n", i, j, j-i );
}
return 0;
}</lang>
=={{header|FreeBASIC}}==
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