RosettaCodeData/Task/Mian-Chowla-sequence/C++/mian-chowla-sequence.cpp

46 lines
1.0 KiB
C++

using namespace std;
#include <iostream>
#include <ctime>
#define n 100
#define nn ((n * (n + 1)) >> 1)
bool Contains(int lst[], int item, int size) {
for (int i = 0; i < size; i++) if (item == lst[i]) return true;
return false;
}
int * MianChowla()
{
static int mc[n]; mc[0] = 1;
int sums[nn]; sums[0] = 2;
int sum, le, ss = 1;
for (int i = 1; i < n; i++) {
le = ss;
for (int j = mc[i - 1] + 1; ; j++) {
mc[i] = j;
for (int k = 0; k <= i; k++) {
sum = mc[k] + j;
if (Contains(sums, sum, ss)) {
ss = le; goto nxtJ;
}
sums[ss++] = sum;
}
break;
nxtJ:;
}
}
return mc;
}
int main() {
clock_t st = clock(); int * mc; mc = MianChowla();
double et = ((double)(clock() - st)) / CLOCKS_PER_SEC;
cout << "The first 30 terms of the Mian-Chowla sequence are:\n";
for (int i = 0; i < 30; i++) { cout << mc[i] << ' '; }
cout << "\n\nTerms 91 to 100 of the Mian-Chowla sequence are:\n";
for (int i = 90; i < 100; i++) { cout << mc[i] << ' '; }
cout << "\n\nComputation time was " << et << " seconds.";
}