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587 pengi 1 
#include <stdio.h>
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#include <stdlib.h>
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double scale( long val, long k, long m );
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long iscale( long val, long k, long m, long fact );
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int main( int argc, char *argv[] ) {
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    long k, m;
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    if( argc != 3 ) {
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        fprintf( stderr, "Usage: %s <k> <m>\n", argv[0] );
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        return 1;
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    }
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    k=atoi(argv[1]);
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    m=atoi(argv[2]);
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    printf( "k=%d m=%d\n", k, m );
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    printf( "scale(    0)=%f\n", scale(     0, k, m ) );
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    printf( "scale(65535)=%f\n", scale( 65535, k, m ) );
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    printf( "scale(1)-scale(0)=%f\n", scale( 1, k, m ) - scale( 0, k, m ) );
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    printf( "iscale(0,100)=%d", iscale( 0, k, m, 100 ) );
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    return 0;
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}
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double scale( long val, long k, long m ) {
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    return (double)m - 32768.0 + ((double)k*(double)val)/256.0;
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}
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long iscale( long val, long k, long m, long fact ) {
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    return m*fact - (fact<<15) + ((k*val*fact)>>8);
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}