void ptrswap(int *&v1, int *&v2) {
int *tmp = v2;
v1 = v2;
v2 = tmp;
}
int main() {
int i = 10;
int j = 20;
int *pi = &i;
int *pj = &j;
cout << *pi << " " << *pj << endl;
ptrswap(pi, pj);
cout << *pi << " " << *pj << endl;
return 0;
}10 20
20 10
int incr(int val) {
return ++val;
}
int incrRef(int &val) {
return ++val;
}
int incrRefConst(const int &val) {
cout << val << endl;
return val;
}
int main() {
short v1 = 0;
const int v2 = 42;
double v4 = 3.4;
int v3 = incr(v1);
v3 = incrRef(v1); // X: no matching function for call to 'incrRef'
v3 = incrRefConst(v1); // 0
int v5 = incr(v4);
v5 = incrRef(v4); // X: no matching function for call to 'incrRef'
v5 = incrRefConst(v4); // 3
cout << v4 << " " << v5 << endl; // 3.4 3
return 0;
}
int *pia = new int[10](); // 10 ints w/ default value 0const int ival = 1024;
const int &refVal = ival;const int &r = 42;
const int &r2 = r + 3;for (vector<string>::const_iterator iter = text.begin();
iter != text.end(); ++iter) {
*iter = " "; // error: *iter is const
}vector<int> nums(10);
const vector<int>::iterator cit = nums.begin();
*cit = 1; // OK
++cit; // error: cit is constconst double pi = 3.14;
double *ptr = π // error: nonconst pointer
const double *cptr = π // OK
double dval = 2.99;
cptr = &dval; // OKint errNumber = 0;
int *const curErr = &errNumber;
curErr = curErr; // error: curErr is const
if (*curErr) {
errorHandler();
*curErr = 0; // OK
}const double pi = 3.14159;
const double *const pi_ptr = πtypedef string *pstring;
const pstring cstr;ii -> V -> I, I -> IV 等慣用進行Tonic -> Sub-dominant -> Dominant -> Tonic 的感覺考慮進去Tonic -> Sub-dominant or Tonic -> Dominant (but it’s more comfortable to use Tonic -> Sub-dominant -> Tonic) (1)Sub-dominant -> Tonic or Sub-dominant -> Dominant (2)Dominant -> Tonic (3)
7-2-#4 and Bm7 is 7-2-#4-6.
int *createArrayAddr(int n) {
int *a = new int(5);
cout << (void*) a << endl;
return a;
}
int &createArrayRef(int &n) {
cout << &n << endl;
return n;
}
int main(int argc, const char * argv[]) {
int *a = createArrayAddr(5);
cout << (void*) a << endl;
int n = 55;
cout << &n << endl;
int &n2 = createArrayRef(n);
cout << &n2 << endl;
return 0;
}
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