#include <cstdio>
int n, k;
int ranks[2021];
int tmp[2021];
void sort(int begin, int end)
{
if (end - begin < 2) return;
int mid = (begin + end) / 2;
sort(begin, mid);
sort(mid, end);
int a = begin;
int b = mid;
int c = 0;
while (a < mid && b < end)
{
if (ranks[a] > ranks[b]) tmp[c++] = ranks[a++];
else tmp[c++] = ranks[b++];
}
while (a < mid) tmp[c++] = ranks[a++];
while (b < end) tmp[c++] = ranks[b++];
c = 0;
while (begin < end) ranks[begin++] = tmp[c++];
}
int solve()
{
int min_score = ranks[k - 1];
int begin = 0;
int end = n;
int mid;
while (begin < end)
{
mid = (begin + end) / 2;
if (ranks[mid] < min_score) end = mid;
else begin = mid + 1;
}
return end;
}
int main()
{
scanf("%d %d", &n, &k);
for (int i = 0; i < n; ++i) scanf("%d", &ranks[i]);
sort(0, n);
int ans = solve();
printf("%d\n", ans);
return 0;
}
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 | #include <cstdio> int n, k; int ranks[2021]; int tmp[2021]; void sort(int begin, int end) { if (end - begin < 2) return; int mid = (begin + end) / 2; sort(begin, mid); sort(mid, end); int a = begin; int b = mid; int c = 0; while (a < mid && b < end) { if (ranks[a] > ranks[b]) tmp[c++] = ranks[a++]; else tmp[c++] = ranks[b++]; } while (a < mid) tmp[c++] = ranks[a++]; while (b < end) tmp[c++] = ranks[b++]; c = 0; while (begin < end) ranks[begin++] = tmp[c++]; } int solve() { int min_score = ranks[k - 1]; int begin = 0; int end = n; int mid; while (begin < end) { mid = (begin + end) / 2; if (ranks[mid] < min_score) end = mid; else begin = mid + 1; } return end; } int main() { scanf("%d %d", &n, &k); for (int i = 0; i < n; ++i) scanf("%d", &ranks[i]); sort(0, n); int ans = solve(); printf("%d\n", ans); return 0; } |
English