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fanzhang312/isFibo.java

Created December 4, 2014 05:14
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Check if a number is a Fibonacci number
Raw
isFibo.java
public static boolean isFibo(long n){
return isPerfectSquare(5*n*n+4) || isPerfectSquare(5*n*n-4);
}
public static boolean isPerfectSquare(double a){
int s = (int) Math.sqrt(a);
return s*s == a;
}
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