Compilare: main.cpp: In function 'int calc(int)': main.cpp:16:38: warning: no return statement in function returning non-void [-Wreturn-type] dp[i][k]=(dp[i][k]+dp[i-1][k2])%mod;}} ^ main.cpp: In function 'int main()': main.cpp:18:31: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("lucky7.in","r",stdin); ^ main.cpp:19:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("lucky7.out","w",stdout); ^ main.cpp:21:25: warning: ignoring return value of 'char* fgets(char*, int, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fgets(ch+1,100003,stdin); ^