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author | Indrajith K L | 2022-12-03 17:00:20 +0530 |
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committer | Indrajith K L | 2022-12-03 17:00:20 +0530 |
commit | f5c4671bfbad96bf346bd7e9a21fc4317b4959df (patch) | |
tree | 2764fc62da58f2ba8da7ed341643fc359873142f /v_windows/v/old/vlib/math/big/big.v | |
download | cli-tools-windows-master.tar.gz cli-tools-windows-master.tar.bz2 cli-tools-windows-master.zip |
Diffstat (limited to 'v_windows/v/old/vlib/math/big/big.v')
-rw-r--r-- | v_windows/v/old/vlib/math/big/big.v | 322 |
1 files changed, 322 insertions, 0 deletions
diff --git a/v_windows/v/old/vlib/math/big/big.v b/v_windows/v/old/vlib/math/big/big.v new file mode 100644 index 0000000..a93aa9e --- /dev/null +++ b/v_windows/v/old/vlib/math/big/big.v @@ -0,0 +1,322 @@ +module big + +// Wrapper for https://github.com/kokke/tiny-bignum-c +#flag -I @VEXEROOT/thirdparty/bignum +#flag @VEXEROOT/thirdparty/bignum/bn.o +#include "bn.h" + +struct C.bn { +mut: + array [32]u32 +} + +// Big unsigned integer number. +type Number = C.bn + +fn C.bignum_init(n &Number) + +fn C.bignum_from_int(n &Number, i u64) + +fn C.bignum_to_int(n &Number) int + +fn C.bignum_from_string(n &Number, s &char, nbytes int) + +fn C.bignum_to_string(n &Number, s &char, maxsize int) + +// c = a + b +fn C.bignum_add(a &Number, b &Number, c &Number) + +// c = a - b +fn C.bignum_sub(a &Number, b &Number, c &Number) + +// c = a * b +fn C.bignum_mul(a &Number, b &Number, c &Number) + +// c = a / b +fn C.bignum_div(a &Number, b &Number, c &Number) + +// c = a % b +fn C.bignum_mod(a &Number, b &Number, c &Number) + +// c = a/b d=a%b +fn C.bignum_divmod(a &Number, b &Number, c &Number, d &Number) + +// c = a & b +fn C.bignum_and(a &Number, b &Number, c &Number) + +// c = a | b +fn C.bignum_or(a &Number, b &Number, c &Number) + +// c = a xor b +fn C.bignum_xor(a &Number, b &Number, c &Number) + +// b = a << nbits +fn C.bignum_lshift(a &Number, b &Number, nbits int) + +// b = a >> nbits +fn C.bignum_rshift(a &Number, b &Number, nbits int) + +fn C.bignum_cmp(a &Number, b &Number) int + +fn C.bignum_is_zero(a &Number) int + +// n++ +fn C.bignum_inc(n &Number) + +// n-- +fn C.bignum_dec(n &Number) + +// c = a ^ b +fn C.bignum_pow(a &Number, b &Number, c &Number) + +// b = integer_square_root_of(a) +fn C.bignum_isqrt(a &Number, b &Number) + +// copy src number to dst number +fn C.bignum_assign(dst &Number, src &Number) + +// new returns a bignum, initialized to 0 +pub fn new() Number { + return Number{} +} + +// conversion actions to/from big numbers: +// from_int converts an ordinary int number `i` to big.Number +pub fn from_int(i int) Number { + n := Number{} + C.bignum_from_int(&n, i) + return n +} + +// from_u64 converts an ordinary u64 number `u` to big.Number +pub fn from_u64(u u64) Number { + n := Number{} + C.bignum_from_int(&n, u) + return n +} + +// from_hex_string converts a hex string to big.Number +pub fn from_hex_string(input string) Number { + mut s := input.trim_prefix('0x') + if s.len == 0 { + s = '0' + } + padding := '0'.repeat((8 - s.len % 8) % 8) + s = padding + s + n := Number{} + C.bignum_from_string(&n, &char(s.str), s.len) + return n +} + +// from_string converts a decimal string to big.Number +pub fn from_string(input string) Number { + mut n := from_int(0) + for _, c in input { + d := from_int(int(c - `0`)) + n = (n * big.ten) + d + } + return n +} + +// .int() converts (a small) big.Number `n` to an ordinary integer. +pub fn (n &Number) int() int { + r := C.bignum_to_int(n) + return r +} + +const ( + ten = from_int(10) +) + +// .str returns a decimal representation of the big unsigned integer number n. +pub fn (n &Number) str() string { + if n.is_zero() { + return '0' + } + mut digits := []byte{} + mut x := n.clone() + + for !x.is_zero() { + // changes to reflect new api + div, mod := divmod(&x, &big.ten) + digits << byte(mod.int()) + `0` + x = div + } + return digits.reverse().bytestr() +} + +// .hexstr returns a hexadecimal representation of the bignum `n` +pub fn (n &Number) hexstr() string { + mut buf := [8192]byte{} + mut s := '' + unsafe { + bp := &buf[0] + // NB: C.bignum_to_string(), returns the HEXADECIMAL representation of the bignum n + C.bignum_to_string(n, &char(bp), 8192) + s = tos_clone(bp) + } + if s.len == 0 { + return '0' + } + return s +} + +// ////////////////////////////////////////////////////////// +// overloaded ops for the numbers: +pub fn (a &Number) + (b &Number) Number { + c := Number{} + C.bignum_add(a, b, &c) + return c +} + +pub fn (a &Number) - (b &Number) Number { + c := Number{} + C.bignum_sub(a, b, &c) + return c +} + +pub fn (a &Number) * (b &Number) Number { + c := Number{} + C.bignum_mul(a, b, &c) + return c +} + +pub fn (a &Number) / (b &Number) Number { + c := Number{} + C.bignum_div(a, b, &c) + return c +} + +pub fn (a &Number) % (b &Number) Number { + c := Number{} + C.bignum_mod(a, b, &c) + return c +} + +// divmod returns a pair of quotient and remainder from div modulo operation +// between two bignums `a` and `b` +pub fn divmod(a &Number, b &Number) (Number, Number) { + c := Number{} + d := Number{} + C.bignum_divmod(a, b, &c, &d) + return c, d +} + +// ////////////////////////////////////////////////////////// +pub fn cmp(a &Number, b &Number) int { + return C.bignum_cmp(a, b) +} + +pub fn (a &Number) is_zero() bool { + return C.bignum_is_zero(a) != 0 +} + +pub fn (mut a Number) inc() { + C.bignum_inc(&a) +} + +pub fn (mut a Number) dec() { + C.bignum_dec(&a) +} + +pub fn pow(a &Number, b &Number) Number { + c := Number{} + C.bignum_pow(a, b, &c) + return c +} + +pub fn (a &Number) isqrt() Number { + b := Number{} + C.bignum_isqrt(a, &b) + return b +} + +// ////////////////////////////////////////////////////////// +pub fn b_and(a &Number, b &Number) Number { + c := Number{} + C.bignum_and(a, b, &c) + return c +} + +pub fn b_or(a &Number, b &Number) Number { + c := Number{} + C.bignum_or(a, b, &c) + return c +} + +pub fn b_xor(a &Number, b &Number) Number { + c := Number{} + C.bignum_xor(a, b, &c) + return c +} + +pub fn (a &Number) lshift(nbits int) Number { + b := Number{} + C.bignum_lshift(a, &b, nbits) + return b +} + +pub fn (a &Number) rshift(nbits int) Number { + b := Number{} + C.bignum_rshift(a, &b, nbits) + return b +} + +pub fn (a &Number) clone() Number { + b := Number{} + C.bignum_assign(&b, a) + return b +} + +// ////////////////////////////////////////////////////////// +pub fn factorial(nn &Number) Number { + mut n := nn.clone() + mut a := nn.clone() + n.dec() + mut i := 1 + for !n.is_zero() { + res := a * n + n.dec() + a = res + i++ + } + return a +} + +pub fn fact(n int) Number { + return factorial(from_int(n)) +} + +// bytes returns an array of the bytes for the number `n`, +// in little endian format, where .bytes()[0] is the least +// significant byte. The result is NOT trimmed, and will contain 0s, even +// after the significant bytes. +// This method is faster than .bytes_trimmed(), but may be less convenient. +// Example: assert big.from_int(1).bytes()[0] == byte(0x01) +// Example: assert big.from_int(1024).bytes()[1] == byte(0x04) +// Example: assert big.from_int(1048576).bytes()[2] == byte(0x10) +pub fn (n &Number) bytes() []byte { + mut res := []byte{len: 128, init: 0} + unsafe { C.memcpy(res.data, n, 128) } + return res +} + +// bytes_trimmed returns an array of the bytes for the number `n`, +// in little endian format, where .bytes_trimmed()[0] is the least +// significant byte. The result is trimmed, so that *the last* byte +// of the result is also the the last meaningfull byte, != 0 . +// Example: assert big.from_int(1).bytes_trimmed() == [byte(0x01)] +// Example: assert big.from_int(1024).bytes_trimmed() == [byte(0x00), 0x04] +// Example: assert big.from_int(1048576).bytes_trimmed() == [byte(0x00), 0x00, 0x10] +pub fn (n &Number) bytes_trimmed() []byte { + mut res := []byte{len: 128, init: 0} + unsafe { C.memcpy(res.data, n, 128) } + mut non_zero_idx := 127 + for ; non_zero_idx >= 0; non_zero_idx-- { + if res[non_zero_idx] != 0 { + break + } + } + res.trim(non_zero_idx + 1) + return res +} |