http://www.lydsy.com/JudgeOnline/problem.php?id=1192
好像学过一个东西:
[0..2^(N+1)-1]内的数都的都可以由2^0,2^1,...,2^N这N+1个数中若干个相加得到。
#include<cstdio> #include<cstdlib> #include<iostream> #include<fstream> #include<algorithm> #include<cstring> #include<string> #include<cmath> #include<queue> #include<stack> #include<map> #include<utility> #include<set> #include<bitset> #include<vector> #include<functional> #include<deque> #include<cctype> #include<climits> #include<complex> //#include<bits/stdc++.h>适用于CF,UOJ,但不适用于pojusing namespace std;typedef long long LL; typedef double DB; typedef pair<int,int> PII; typedef complex<DB> CP;#define mmst(a,v) memset(a,v,sizeof(a)) #define mmcy(a,b) memcpy(a,b,sizeof(a)) #define fill(a,l,r,v) fill(a+l,a+r+1,v) #define re(i,a,b) for(i=(a);i<=(b);i++) #define red(i,a,b) for(i=(a);i>=(b);i--) #define ire(i,x) for(typedef(x.begin()) i=x.begin();i!=x.end();i++) #define fi first #define se second #define m_p(a,b) make_pair(a,b) #define SF scanf #define PF printf #define two(k) (1<<(k))template<class T>inline T sqr(T x){return x*x;} template<class T>inline void upmin(T &t,T tmp){if(t>tmp)t=tmp;} template<class T>inline void upmax(T &t,T tmp){if(t<tmp)t=tmp;}const DB EPS=1e-9; inline int sgn(DB x){if(abs(x)<EPS)return 0;return(x>0)?1:-1;} const DB Pi=acos(-1.0);inline int gint(){int res=0;bool neg=0;char z;for(z=getchar();z!=EOF && z!='-' && !isdigit(z);z=getchar());if(z==EOF)return 0;if(z=='-'){neg=1;z=getchar();}for(;z!=EOF && isdigit(z);res=res*10+z-'0',z=getchar());return (neg)?-res:res; } inline LL gll(){LL res=0;bool neg=0;char z;for(z=getchar();z!=EOF && z!='-' && !isdigit(z);z=getchar());if(z==EOF)return 0;if(z=='-'){neg=1;z=getchar();}for(;z!=EOF && isdigit(z);res=res*10+z-'0',z=getchar());return (neg)?-res:res; }int m,cnt,p;int main(){freopen("bzoj1192.in","r",stdin);freopen("bzoj1192.out","w",stdout);m=gint();cnt=0;p=2;while(p-1<m)p<<=1,cnt++;PF("%d\n",cnt+1);return 0;}