Compilare: main.cpp: In function 'void build(int, int, int)': main.cpp:35:15: warning: unused variable 'sum' [-Wunused-variable] long long sum = 0; ^~~ main.cpp: In function 'void update(int, int, int, int, int)': main.cpp:81:15: warning: unused variable 'sum' [-Wunused-variable] long long sum = 0; ^~~ main.cpp: In function 'int main()': main.cpp:129:32: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d%d\n",&n,&q); ^ main.cpp:131:32: warning: ignoring return value of 'char* fgets(char*, int, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fgets(a + 1 , n + 10 , fin); ^ main.cpp:132:32: warning: ignoring return value of 'char* fgets(char*, int, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fgets(b + 1 , n + 10 , fin); ^ main.cpp:133:32: warning: ignoring return value of 'char* fgets(char*, int, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fgets(c + 1 , n + 10 , fin); ^ main.cpp:167:36: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buff , 1 , 3000000 , fin); ^