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Improve ernd as &rnd( 2) always returned same pattern.
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parent
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14
eval.c
14
eval.c
@ -1321,18 +1321,18 @@ char *mklower(char *str)
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/*
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/*
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* returns a random integer
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* returns a random integer
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* ernd( 0) [ 0 .. 2147483647]
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* ernd( 0) [ 0 .. 2147483647]
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* ernd( i) [ 1 .. abs( i)]
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* ernd( -2147483648) [ 0 .. 2147483647]
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* ernd( 1) [ 1]
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* ernd( 1) [ 1]
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* ernd( -2147483648) [ 1 .. 2147483647] actually 2147482413
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* ernd( i) [ 1 .. abs( i)]
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*/
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*/
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static int ernd( int i) {
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static int ernd( int i) {
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seed = seed * 1721 + 10007 ;
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int s ;
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seed &= ~(1 << 31) ; /* avoid abs() which introduces 176719 periodicity */
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if( i == 0)
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return seed ;
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seed = seed * 1721 + 10007 ;
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s = ((seed >> 16) & 0x0000FFFF) | (seed << 16) ;
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s &= ~(1 << 31) ; /* avoid abs() */
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i = i < 0 ? -i : i ; /* abs( i) */
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i = i < 0 ? -i : i ; /* abs( i) */
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return seed % i + 1 ;
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return (i <= 0) ? s : s % i + 1 ;
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}
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}
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/*
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/*
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