TopCoder SAM 632 DIV2, topcoderdiv2

TopCoder SAM 632 DIV2, topcoderdiv2

250: simple question

class RunningAroundPark {public:int numberOfLap(int N, vector <int> d){    int n=d.size();    int ans=1,last=-1;    for(int i=0;i<n;i++)        {            if(d[i]<=last)            {                ans++;                last=d[i];            }            else last=d[i];        }        return ans;}};

500: Find the rule, simple question

class PotentialGeometricSequence {public:int numberOfSubsequences(vector <int> d){        int n=d.size();        if(n==1) return 1;        int ans=0,last=1,slope=d[1]-d[0];        for(int i=2;i<n;i++)        {            int newslope=d[i]-d[i-1];            if(newslope==slope)            {                last++;            }            else            {                last++;                int jia=(last+1)*last/2;                if(ans) jia--;                ans+=jia;                last=1;                slope=newslope;            }        }        last++;        int jia=(last+1)*last/2;        if(ans) jia--;        ans+=jia;        return ans;}};

1000: backpack

typedef long long int LL;const LL mod=1000000007LL;class GoodSubset {public:int numberOfSubsets(int goodValue, vector <int> d){    int n=d.size();    map<LL,LL> mp;    map<LL,LL>::reverse_iterator it;        mp[1]=1;        for(int i=0;i<n;i++)        {            for(it=mp.rbegin();it!=mp.rend();it++)            {                LL t=it->first*d[i];                if(goodValue%t==0)                {                    mp[t]=(mp[t]+it->second)%mod;                }            }        }        mp[1]--;        return mp[goodValue];}};