31 lines
397 B
Plaintext
31 lines
397 B
Plaintext
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int lim;
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int fun(int n,int dep){
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if(n==1) return dep;
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else{
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if(n%2==0) return fun(n/2,dep+1);
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else{
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if(n*3+1<=lim)
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return fun(n*3+1,dep+1);
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else
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return 0;
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}
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}
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}
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const int mod = 1000000007;
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int main(){
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lim = getint();
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int ans = 0;
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int i = 1;
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starttime();
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while(i<=lim){
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ans = (ans+fun(i,0))%mod;
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i = i+1;
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}
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stoptime();
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putint(ans);
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putch(10);
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}
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