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path: root/src/pkg/bignum/bignum.go
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Diffstat (limited to 'src/pkg/bignum/bignum.go')
-rwxr-xr-xsrc/pkg/bignum/bignum.go100
1 files changed, 50 insertions, 50 deletions
diff --git a/src/pkg/bignum/bignum.go b/src/pkg/bignum/bignum.go
index bb7fb68f0..a85e1d2b9 100755
--- a/src/pkg/bignum/bignum.go
+++ b/src/pkg/bignum/bignum.go
@@ -64,17 +64,17 @@ type (
const (
logW = 64; // word width
logH = 4; // bits for a hex digit (= small number)
- logB = logW-logH; // largest bit-width available
+ logB = logW - logH; // largest bit-width available
// half-digits
- _W2 = logB/2; // width
- _B2 = 1<<_W2; // base
- _M2 = _B2-1; // mask
+ _W2 = logB / 2; // width
+ _B2 = 1 << _W2; // base
+ _M2 = _B2 - 1; // mask
// full digits
- _W = _W2*2; // width
- _B = 1<<_W; // base
- _M = _B-1; // mask
+ _W = _W2 * 2; // width
+ _B = 1 << _W; // base
+ _M = _B - 1; // mask
)
@@ -136,7 +136,7 @@ func Nat(x uint64) Natural {
// split x into digits
z := make(Natural, n);
for i := 0; i < n; i++ {
- z[i] = digit(x&_M);
+ z[i] = digit(x & _M);
x >>= _W;
}
@@ -162,7 +162,7 @@ func (x Natural) Value() uint64 {
z := uint64(0);
s := uint(0);
for i := 0; i < n && s < 64; i++ {
- z += uint64(x[i])<<s;
+ z += uint64(x[i]) << s;
s += _W;
}
@@ -236,12 +236,12 @@ func Nadd(zp *Natural, x, y Natural) {
c := digit(0);
i := 0;
for i < m {
- t := c+x[i]+y[i];
+ t := c + x[i] + y[i];
c, z[i] = t>>_W, t&_M;
i++;
}
for i < n {
- t := c+x[i];
+ t := c + x[i];
c, z[i] = t>>_W, t&_M;
i++;
}
@@ -277,12 +277,12 @@ func Nsub(zp *Natural, x, y Natural) {
c := digit(0);
i := 0;
for i < m {
- t := c+x[i]-y[i];
+ t := c + x[i] - y[i];
c, z[i] = digit(int64(t)>>_W), t&_M; // requires arithmetic shift!
i++;
}
for i < n {
- t := c+x[i];
+ t := c + x[i];
c, z[i] = digit(int64(t)>>_W), t&_M; // requires arithmetic shift!
i++;
}
@@ -307,7 +307,7 @@ func (x Natural) Sub(y Natural) Natural {
//
func muladd11(x, y, c digit) (digit, digit) {
z1, z0 := MulAdd128(uint64(x), uint64(y), uint64(c));
- return digit(z1<<(64-logB) | z0>>logB), digit(z0&_M);
+ return digit(z1<<(64-logB) | z0>>logB), digit(z0 & _M);
}
@@ -429,15 +429,15 @@ func (x Natural) Mul(y Natural) Natural {
func unpack(x Natural) []digit2 {
n := len(x);
- z := make([]digit2, n*2 + 1); // add space for extra digit (used by DivMod)
+ z := make([]digit2, n*2+1); // add space for extra digit (used by DivMod)
for i := 0; i < n; i++ {
t := x[i];
- z[i*2] = digit2(t&_M2);
- z[i*2 + 1] = digit2(t>>_W2&_M2);
+ z[i*2] = digit2(t & _M2);
+ z[i*2+1] = digit2(t >> _W2 & _M2);
}
// normalize result
- k := 2*n;
+ k := 2 * n;
for k > 0 && z[k-1] == 0 {
k--
}
@@ -446,7 +446,7 @@ func unpack(x Natural) []digit2 {
func pack(x []digit2) Natural {
- n := (len(x)+1)/2;
+ n := (len(x) + 1) / 2;
z := make(Natural, n);
if len(x)&1 == 1 {
// handle odd len(x)
@@ -454,7 +454,7 @@ func pack(x []digit2) Natural {
z[n] = digit(x[n*2]);
}
for i := 0; i < n; i++ {
- z[i] = digit(x[i*2 + 1])<<_W2 | digit(x[i*2])
+ z[i] = digit(x[i*2+1])<<_W2 | digit(x[i*2])
}
return normalize(z);
}
@@ -474,7 +474,7 @@ func mul21(z, x []digit2, y digit2) digit2 {
func div21(z, x []digit2, y digit2) digit2 {
c := digit(0);
d := digit(y);
- for i := len(x)-1; i >= 0; i-- {
+ for i := len(x) - 1; i >= 0; i-- {
t := c<<_W2 + digit(x[i]);
c, z[i] = t%d, digit2(t/d);
}
@@ -515,7 +515,7 @@ func divmod(x, y []digit2) ([]digit2, []digit2) {
if m == 1 {
// division by single digit
// result is shifted left by 1 in place!
- x[0] = div21(x[1 : n+1], x[0:n], y[0])
+ x[0] = div21(x[1:n+1], x[0:n], y[0])
} else if m > n {
// y > x => quotient = 0, remainder = x
@@ -530,7 +530,7 @@ func divmod(x, y []digit2) ([]digit2, []digit2) {
// TODO Instead of multiplying, it would be sufficient to
// shift y such that the normalization condition is
// satisfied (as done in Hacker's Delight).
- f := _B2/(digit(y[m-1])+1);
+ f := _B2 / (digit(y[m-1]) + 1);
if f != 1 {
mul21(x, x, digit2(f));
mul21(y, y, digit2(f));
@@ -538,19 +538,19 @@ func divmod(x, y []digit2) ([]digit2, []digit2) {
assert(_B2/2 <= y[m-1] && y[m-1] < _B2); // incorrect scaling
y1, y2 := digit(y[m-1]), digit(y[m-2]);
- for i := n-m; i >= 0; i-- {
- k := i+m;
+ for i := n - m; i >= 0; i-- {
+ k := i + m;
// compute trial digit (Knuth)
var q digit;
{
x0, x1, x2 := digit(x[k]), digit(x[k-1]), digit(x[k-2]);
if x0 != y1 {
- q = (x0<<_W2 + x1)/y1
+ q = (x0<<_W2 + x1) / y1
} else {
- q = _B2-1
+ q = _B2 - 1
}
- for y2*q > (x0<<_W2 + x1 - y1*q)<<_W2 + x2 {
+ for y2*q > (x0<<_W2+x1-y1*q)<<_W2+x2 {
q--
}
}
@@ -567,7 +567,7 @@ func divmod(x, y []digit2) ([]digit2, []digit2) {
// add y
c := digit(0);
for j := 0; j < m; j++ {
- t := c+digit(x[i+j])+digit(y[j]);
+ t := c + digit(x[i+j]) + digit(y[j]);
c, x[i+j] = t>>_W2, digit2(t&_M2);
}
assert(c+digit(x[k]) == 0);
@@ -623,7 +623,7 @@ func shl(z, x Natural, s uint) digit {
n := len(x);
c := digit(0);
for i := 0; i < n; i++ {
- c, z[i] = x[i]>>(_W-s), x[i]<<s&_M | c
+ c, z[i] = x[i]>>(_W-s), x[i]<<s&_M|c
}
return c;
}
@@ -636,7 +636,7 @@ func (x Natural) Shl(s uint) Natural {
m := n + s/_W;
z := make(Natural, m+1);
- z[m] = shl(z[m-n : m], x, s%_W);
+ z[m] = shl(z[m-n:m], x, s%_W);
return normalize(z);
}
@@ -646,8 +646,8 @@ func shr(z, x Natural, s uint) digit {
assert(s <= _W);
n := len(x);
c := digit(0);
- for i := n-1; i >= 0; i-- {
- c, z[i] = x[i]<<(_W-s)&_M, x[i]>>s | c
+ for i := n - 1; i >= 0; i-- {
+ c, z[i] = x[i]<<(_W-s)&_M, x[i]>>s|c
}
return c;
}
@@ -663,7 +663,7 @@ func (x Natural) Shr(s uint) Natural {
}
z := make(Natural, m);
- shr(z, x[n-m : n], s%_W);
+ shr(z, x[n-m:n], s%_W);
return normalize(z);
}
@@ -680,7 +680,7 @@ func (x Natural) And(y Natural) Natural {
z := make(Natural, m);
for i := 0; i < m; i++ {
- z[i] = x[i]&y[i]
+ z[i] = x[i] & y[i]
}
// upper bits are 0
@@ -706,7 +706,7 @@ func (x Natural) AndNot(y Natural) Natural {
z := make(Natural, n);
for i := 0; i < m; i++ {
- z[i] = x[i]&^y[i]
+ z[i] = x[i] &^ y[i]
}
copy(z[m:n], x[m:n]);
@@ -725,7 +725,7 @@ func (x Natural) Or(y Natural) Natural {
z := make(Natural, n);
for i := 0; i < m; i++ {
- z[i] = x[i]|y[i]
+ z[i] = x[i] | y[i]
}
copy(z[m:n], x[m:n]);
@@ -744,7 +744,7 @@ func (x Natural) Xor(y Natural) Natural {
z := make(Natural, n);
for i := 0; i < m; i++ {
- z[i] = x[i]^y[i]
+ z[i] = x[i] ^ y[i]
}
copy(z[m:n], x[m:n]);
@@ -763,10 +763,10 @@ func (x Natural) Cmp(y Natural) int {
m := len(y);
if n != m || n == 0 {
- return n-m
+ return n - m
}
- i := n-1;
+ i := n - 1;
for i > 0 && x[i] == y[i] {
i--
}
@@ -794,7 +794,7 @@ func log2(x uint64) uint {
x >>= 1;
n++;
}
- return n-1;
+ return n - 1;
}
@@ -818,7 +818,7 @@ func divmod1(x Natural, d digit) (Natural, digit) {
assert(0 < d && isSmall(d-1));
c := digit(0);
- for i := len(x)-1; i >= 0; i-- {
+ for i := len(x) - 1; i >= 0; i-- {
t := c<<_W + x[i];
c, x[i] = t%d, t/d;
}
@@ -836,7 +836,7 @@ func (x Natural) ToString(base uint) string {
// allocate buffer for conversion
assert(2 <= base && base <= 16);
- n := (x.Log2() + 1)/log2(uint64(base)) + 1; // +1: round up
+ n := (x.Log2()+1)/log2(uint64(base)) + 1; // +1: round up
s := make([]byte, n);
// don't destroy x
@@ -882,14 +882,14 @@ func (x Natural) Format(h fmt.State, c int) { fmt.Fprintf(h, "%s", x.ToString(fm
func hexvalue(ch byte) uint {
- d := uint(1<<logH);
+ d := uint(1 << logH);
switch {
case '0' <= ch && ch <= '9':
- d = uint(ch-'0')
+ d = uint(ch - '0')
case 'a' <= ch && ch <= 'f':
- d = uint(ch-'a')+10
+ d = uint(ch-'a') + 10
case 'A' <= ch && ch <= 'F':
- d = uint(ch-'A')+10
+ d = uint(ch-'A') + 10
}
return d;
}
@@ -940,7 +940,7 @@ func NatFromString(s string, base uint) (Natural, uint, int) {
func pop1(x digit) uint {
n := uint(0);
for x != 0 {
- x &= x-1;
+ x &= x - 1;
n++;
}
return n;
@@ -951,7 +951,7 @@ func pop1(x digit) uint {
//
func (x Natural) Pop() uint {
n := uint(0);
- for i := len(x)-1; i >= 0; i-- {
+ for i := len(x) - 1; i >= 0; i-- {
n += pop1(x[i])
}
return n;
@@ -986,7 +986,7 @@ func MulRange(a, b uint) Natural {
case a+1 == b:
return Nat(uint64(a)).Mul(Nat(uint64(b)))
}
- m := (a+b)>>1;
+ m := (a + b) >> 1;
assert(a <= m && m < b);
return MulRange(a, m).Mul(MulRange(m+1, b));
}
generated by cgit v1.2.3 (git 2.39.1) at 2025-06-21 21:00:54 +0000