Submission #120218

#	Time	Username	Problem	Language	Result	Execution time	Memory
120218		errorgorn	JOIOJI (JOI14_joioji)	C++14	100 / 100	28 ms	11176 KiB

joioji

        #include <cstdio>
        #include <unordered_map>
        #include <utility>
        #include <string>
        #include <iostream>
        #include <cstring>
        #include <algorithm>
        using namespace std;
        typedef pair<int,int> ii;
        int n;
        char c;
        string s;
        struct custom_hash{
            size_t operator()(const pair<int,int> &i)const{
                return hash<long long>()(((long long)i.first)^(((long long)i.second)<<32));
            }
        };
        unordered_map<ii,int,custom_hash> suffix;
        int arr[3];
        int pre[3];
        int main(){
            suffix.reserve(4096);
            suffix.max_load_factor(0.25);
            //freopen("input.txt","r",stdin);
            scanf("%d",&n);
            getchar();
            c=getchar();
            while (c!='\n'){
                s+=c;
                if (c=='J') arr[0]++;
                else if (c=='O') arr[1]++;
                else arr[2]++;
                c=getchar();
            }
            suffix[ii(0,0)]=0;
            for (int x=0;x<3;x++) pre[x]=arr[x];
            for (int x=0;x<s.size();x++){
                if (s[x]=='J') pre[0]--;
                else if (s[x]=='O') pre[1]--;
                else pre[2]--;
                suffix[ii(pre[0]-pre[1],pre[0]-pre[2])]=x+1;
            }
            memset(pre,0,sizeof(pre));
            int ans=0;
            int a=arr[0]-arr[1],b=arr[0]-arr[2];
            for (int x=0;x<s.size();x++){
                ans=max(ans,suffix[ii(a-(pre[0]-pre[1]),b-(pre[0]-pre[2]))]-x);
                if (s[x]=='J') pre[0]++;
                else if (s[x]=='O') pre[1]++;
                else pre[2]++;
            }
            printf("%d\n",ans);
        }

Compilation message (stderr)

joioji.cpp: In function 'int main()':
joioji.cpp:37:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for (int x=0;x<s.size();x++){
                          ~^~~~~~~~~
joioji.cpp:46:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for (int x=0;x<s.size();x++){
                          ~^~~~~~~~~
joioji.cpp:25:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d",&n);
             ~~~~~^~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 15 / 15
• Subtask 3: 80 / 80