42 lines
748 B
C++
42 lines
748 B
C++
#include<stdio.h>
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#include<string.h>
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typedef __int64 ll;
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ll m;
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ll cal(ll s,ll x)
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{
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return (2*s+x-1)*x;
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}
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ll binary_search(ll x)
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{
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ll left,right,mid,tmp;
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left=1,right=m/2+1;
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while(left<=right)
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{
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mid=(left+right)>>1;
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tmp=cal(mid,x);
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if(tmp==2*m)
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return mid;
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else if(tmp<2*m)
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left=mid+1;
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else
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right=mid-1;
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}
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return -1;
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}
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int main()
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{
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ll i,tmp,num,cnt=1;
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while(scanf("%I64d",&m)!=EOF)
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{
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num=0;
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for(i=2;i*i<=2*m+10;i++)
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{
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tmp=binary_search(i);
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if(tmp!=-1)
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num++;
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}
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printf("%I64d\n",num+1);
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}
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return 0;
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}
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