First, the number of algorithms
1. Seeking two maximum number of conventions
Function GCD (A, B: Integer): Integer;
Begin
IF b = 0 THEN GCD: = a
Else GCD: = GCD (B, A MOD B);
END;
2. Seeking two minimum common multiple
Function LCM (A, B: Integer): Integer;
Begin
IF a
LCM: = A;
While LCM MOD B> 0 DO INC (LCM, A);
END;
3. Justice
A. Decree a number in a small range is the number:
Function Prime (N: Integer): Boolean;
VAR i: integer;
Begin
For i: = 2 to trunc (SQRT (N)) DO
IF n mod i = 0 THEN BEGIN
PRIME: = false; exit;
END;
PRIME: = TRUE;
END;
B. Judging whether the number within the longint range is the number of prime numbers (including the number of prime tables within 500,000):
Procedure getprime;
VAR
i, j: longint;
P: array [1..50000] of boolean;
Begin
Fillchar (P, SizeOf (P), TRUE);
P [1]: = false;
i: = 2;
While i <5000 do begin
IF P [i] THEN Begin
J: = i * 2;
While J <50000 Do Begin
P [J]: = FALSE
INC (J, I);
END;
END;
INC (I);
END;
l: = 0;
For i: = 1 to 5000 do
IF P [i] THEN Begin
INC (L); Pr [L]: = I;
END;
End; {getprime}
Function prime (x: longint): integer;
VAR i: integer;
Begin
PRIME: = FALSE;
For i: = 1 to L DO
IF PR [I]> = x Then Break
ELSE IF X MOD PR [I] = 0 THEN EXIT;
PRIME: = TRUE;
End; {prime}
