Your code has plenty of errors. Just try to run and you'll see them and can fix them one by one:
- line 34: extra single quote, remove it.
- line 14: extra closing parenthesis after numbers[i], remove it.
- line 49: space in variable name is not allowed
- line 50: space in variable name is not allowed
- line 50: the method Fast() does not exist. Did you mean MaxPairwiseProductFast()?
- line 67: setting up the return value to 0 is return 0; not return = 0;
- extra (unneeded) closing brace in the last line. Remove it.
After you fix these, the code runs. (I didn't have the time to check if it does the right thing -- not even sure what your code is supposed to do -- but the program starts, it has some output and it does not crash.)
#include <iostream>
#include <vector>
using std::vector;
using std::cin;
using std::cout;
long long MaxPairwiseProduct(const vector<int>& numbers) {
long long result = 0;
int n = numbers.size();
for (int i = 0;i<n;++i) {
for (int j = i+1;j<n;++j) {
if (((long long)numbers[i] * numbers[j]) > result) {
result = ((long long)(numbers[i]))*numbers[j];
}
}
}
return result;
}
long long MaxPairwiseProductFast(const vector<int>& numbers)
{int n = numbers.size();
int max_index1 = -1;
for(int i = 0;i<n;++i)
if ((max_index1 == -1) || (numbers[i] > numbers[max_index1]))
max_index1 = i;
int max_index2 = -1;
for(int j = 0;j<n;++j)
if ((j !=max_index1) && (max_index2 == -1) || (numbers[j] > numbers[max_index1]))
max_index2 = j;
cout <<max_index1 << ' '<<max_index2 <<"\n";
}
int main() {
while (true) {
int n = rand() % 4 + 2;
cout << n << "\n";
vector<int>a;
for (int i = 0;i<n;++i) {
a.push_back(rand()% 10);
}
for(int i=0 ; i<n ; ++i) {
cout <<a[i]<< ' ';
}
cout <<"\n";
long long res1 = MaxPairwiseProduct(a);
long long res2 = MaxPairwiseProductFast(a);
if (res1 !=res2) {
cout<< "wrong answer: "<< res1 << ' ' << res2 << "\n";
break;
}
else {
cout << "OK\n";
}
}
int n;
cin >> n;
vector<int> numbers(n);
for (int i=0;i<n; ++i) {
cin >> numbers[i];
}
long long result = MaxPairwiseProductFast(numbers);
cout << result << "\n";
return 0;
}