c++ | 100% faster than all | easy to understand
```\nclass Solution {\npublic:\n    int minNumberOfHours(int initialEnergy, int initialExperience, vector& energy, vector& experience) {\n        int traning=0,
```\nclass Solution {\npublic:\n    int minNumberOfHours(int initialEnergy, int initialExperience, vector<int>& energy, vector<int>& experience) {\n        int traning=0,n=energy.size();\n        for(int i=0;i<n;i++)\n        {\n            if(energy[i]>=initialEnergy)\n            {\n                int diff=energy[i]-initialEnergy;\n                traning+=diff+1;\n                initialEnergy+=diff+1;\n            }\n            if(experience[i]>=initialExperience)\n            {\n                int diff=experience[i]-initialExperience;\n                traning+=diff+1;\n                initialExperience+=diff+1;\n            }\n            initialEnergy-=energy[i];\n            initialExperience+=experience[i];\n        }\n        return traning;\n    }\n};
[]