char * _add_str(char * a, char * b, unsigned long p, unsigned long q) {
unsigned long len = _maxval(p,q)+1;
char * m = malloc(len);
int carry=0;
unsigned long ai,bi,t;
memset(m,0,len);
bi = q-1;
ai = p-1;
for( t=len-1;t!=0;--t) {
if( ai != -1 && bi != -1 ) {
m[t] = _ctoi(a[ai--]) + _ctoi(b[bi--]) + carry;
} else if( ai != -1 ) {
m[t] = _ctoi(a[ai--]) + carry;
} else if( bi != -1 ) {
m[t] = _ctoi(b[bi--]) + carry;
} else {
break;
}
if( m[t] >= 10 ) {
carry = m[t]/10;
m[t] -= 10;
} else {
carry = 0;
}
}
if( carry > 0 ) {
m[0] = carry;
}
return _to_ascii(m, len);
}
dComparisonResult
dString::compare(const dString* inStr, dEStringCompareOptions options, dRange range) const {
if (!inStr) return kCompareLessThan;
if (dZeroRange.location == range.location && dZeroRange.length == range.length)
range = dMakeRange(0, length());
dUInteger inStrLen = inStr->length();
TCHAR selfBuff[range.length + 1];
TCHAR inStrBuff[inStrLen + 1];
getCharacters(selfBuff, range);
inStr->getCharacters(inStrBuff);
if (kECaseInsensitiveSearch & options) {
_upperCaseString(selfBuff);
_upperCaseString(inStrBuff);
}
dInteger numResult;
dUInteger i, j, il, jl;
if (kENumericSearch & options) {
for (i = 0, j = 0; i < range.length && j < inStrLen; ++i, ++j) {
if (_isNumChar(selfBuff[i]) && _isNumChar(inStrBuff[j])) {
il = range.length;
jl = inStrLen;
numResult = _ctoi(&selfBuff[i], &il) - _ctoi(&inStrBuff[j], &jl);
if (numResult < 0 ) return kCompareGreaterThan;
else if (numResult > 0) return kCompareLessThan;
i += il;
j += jl;
}
if (selfBuff[i] < inStrBuff[j]) return kCompareGreaterThan;
else if (selfBuff[i] > inStrBuff[j]) return kCompareLessThan;
}
} else {
for (i = 0; i < range.length && i < inStrLen; ++i) {
if (selfBuff[i] < inStrBuff[i]) return kCompareGreaterThan;
else if (selfBuff[i] > inStrBuff[i]) return kCompareLessThan;
}
}
if (range.length == inStrLen)
return kCompareEqualTo;
return i < inStrLen ? kCompareGreaterThan : kCompareLessThan;
}
char * _mul_str(char * a, char * b, unsigned long p, unsigned long q) {
unsigned long len = p+q;
char * m = malloc(len);
int carry=0;
unsigned long ai,bi;
memset(m,0,len);
for( bi = q-1; bi != -1; --bi ) {
for( ai = p-1; ai != -1; --ai ) {
m[ai + bi+1] += carry + _ctoi(a[ai]) * _ctoi(b[bi]);
carry = m[ai + bi+1] / 10;
m[ai + bi+1] %= 10;
}
m[bi] += carry;
carry=0;
}
return _to_ascii(m, len);
}