10017 - How many ways?
#include <iostream> using namespace std; void Slove(int n, int x) { int answer=0; for (int i=1; i<=n; ++i) for (int j=i+1; j<=n; ++j) for (int k=j+1; k<=n; ++k) if (i+j+k == x) ++answer; cout << answer << endl; } int main(void) { int n, x; while (cin >> n >> x && n) Slove(n,x); return 0; }
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