http://codeforces.com/gym/100283/problem/F
思路是二分第几行,二分出来的行是总和 >= n的,那么第k - 1行一定要选,那么再在第k行中二分那一列、
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <assert.h>
#define IOS ios::sync_with_stdio(false)
using namespace std;
#define inf (0x3f3f3f3f)
typedef long long int LL;
#include <iostream>
#include <sstream>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <string>
#include <bitset>
LL f1(LL n) {
return n * (n + 1) / 2 * (2 * n + 1) / 3;
}
LL f2(int which, int pos) {
if (pos <= which) {
return 1LL * pos * (1 + pos) / 2;
} else {
LL t = 2 * which - 1 - pos;
return 1LL * which * (1 + which) - which - f2(which, t);
}
}
void work() {
LL n;
scanf("%I64d", &n);
int be = 1, en = 2e6 + 20;
while (be <= en) {
int mid = (be + en) >> 1;
LL res = f1(mid);
if (res >= n) {
en = mid - 1;
} else be = mid + 1;
}
// cout << be << endl;
// cout << f1(be) << endl;
LL ans = ((LL)be - 1) * (be - 1);
// cout << n << endl;
// cout << f1(be - 1) << endl;
n -= f1(be - 1);
// cout << n << endl;
// cout << f2(4, 8) << endl;
int L = 1, R = 2 * be - 1;
while (L <= R) {
int mid = (L + R) >> 1;
LL res = f2(be, mid);
if (res >= n) {
R = mid - 1;
} else L = mid + 1;
}
ans += L;
static int f = 0;
printf("Case %d: %I64d\n", ++f, ans);
}
int main() {
#ifdef local
freopen("data.txt", "r", stdin);
// freopen("data.txt", "w", stdout);
#endif
// freopen("army.in", "r", stdin);
int t;
scanf("%d", &t);
while (t--) work();
return 0;
}
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