【杂题】 codeforces 448D Multiplication Table

简单二分。。比赛时没想到。。

#include <iostream>  #include <queue>  #include <stack>  #include <map>  #include <set>  #include <bitset>  #include <cstdio>  #include <algorithm>  #include <cstring>  #include <climits>  #include <cstdlib>#include <cmath>#define maxn 1000005#define eps 1e-10#define mod 1000000009#define INF 99999999  #define lowbit(x) (x&(-x))  #define lson o<<1, L, mid  #define rson o<<1 | 1, mid+1, R  typedef long long LL;using namespace std;int main(void){LL n, m, k, top, mid, bot, i, cnt, ans;scanf("%I64d%I64d%I64d", &n, &m, &k);bot = 1, top = n*m;while(bot<=top) {mid = (bot+top)>>1, cnt = 0;for(i = 1; i <= n; i++)cnt += min(mid/i, m);if(cnt >= k) top = mid-1, ans = mid;else bot = mid+1;}printf("%I64d\n", ans);return 0;}