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• double func(); −→ double (*pfunc)();

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int func() {

return 0;

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int (*fp1)() = &func;

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using namespace std;

double piX(int);

int main() {

double (*pp)(int) = NULL;

pp = &piX; // pp = piX; ¬½ ¤Ñò¬Ýå int x = 2;

cout << "The result with " << x << " is " << (*pp)(2) << ".\n";

return 0;

}

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cout << "We multiply pi with " << x << ".\n";

return 3.14*(double)x;

}

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int add(int a, int b) {

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int main() {

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int (*fp)(int,int);

fp= &add; // fp = add ¬½ ¤Ñò¬Ýå

cout << "(*fp)(2,3) = " << (*fp)(2,3) << endl; // fp(2,3) ¡½ ¤Ñò¬Ýå cout << "fp = "<< fp << endl;

cout << "(&fp) = "<< (&fp) << endl;

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} s

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using namespace std;

double p1(int);

double p2(int);

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void estimate(int, double (*)(int));

int main() {

cout << "Enter LOC: ";

int code;

cin >> code;

cout << "Estimated time for P1:\n";

estimate(code, &p1);

cout << "Estimated time for P2:\n";

estimate(code, &p2);

return 0;

}

double p1(int lns) {

return 0.05 * lns;

}

double p2(int lns) {

return 0.03 * lns + 0.0004 * lns * lns;

}

void estimate(int lines, double (*pf)(int)) {

cout << "For " << lines << " lines, "

"it takes " << (*pf)(lines) << " time.\n";

}

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float result = 0;

// execute operation switch(opCode) {

case ’+’ : result = plus(a,b); break;

case ’-’ : result = minus(a,b); break;

case ’*’ : result = multiply(a,b); break;

case ’/’ : result = divide(a,b); break;

}

cout << result << endl; // display result

}

int main() {

operate(2, 5, ’+’);

} 0

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cout << result << endl; // display result }

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int (*func())() { return &hello; } int main()

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pFunc=&func;

cout << ((*(*pFunc))())() << endl;

return 0;

}

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