34 lines
449 B
C
34 lines
449 B
C
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#include "f2c.h"
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#ifdef KR_headers
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longint pow_qq(ap, bp) longint *ap, *bp;
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#else
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longint pow_qq(longint *ap, longint *bp)
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#endif
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{
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longint pow, x, n;
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unsigned long long u; /* system-dependent */
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x = *ap;
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n = *bp;
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if (n <= 0) {
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if (n == 0 || x == 1)
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return 1;
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if (x != -1)
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return x == 0 ? 1/x : 0;
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n = -n;
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}
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u = n;
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for(pow = 1; ; )
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{
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if(u & 01)
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pow *= x;
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if(u >>= 1)
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x *= x;
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else
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break;
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}
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return(pow);
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}
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