36 lines
519 B
C
36 lines
519 B
C
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#include "os.h"
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#include <mp.h>
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#include "dat.h"
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// prereq: alen >= blen, sum has at least blen+1 digits
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void
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mpvecadd(mpdigit *a, int alen, mpdigit *b, int blen, mpdigit *sum)
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{
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int i, carry;
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mpdigit x, y;
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carry = 0;
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for(i = 0; i < blen; i++){
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x = *a++;
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y = *b++;
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x += carry;
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if(x < carry)
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carry = 1;
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else
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carry = 0;
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x += y;
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if(x < y)
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carry++;
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*sum++ = x;
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}
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for(; i < alen; i++){
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x = *a++ + carry;
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if(x < carry)
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carry = 1;
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else
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carry = 0;
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*sum++ = x;
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}
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*sum = carry;
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}
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