Compilare: user.cpp: In function ‘void read()’: user.cpp:9:9: warning: unused variable ‘i’ [-Wunused-variable] int i; ^ user.cpp: In function ‘int solve(int, char*)’: user.cpp:17:9: warning: unused variable ‘N’ [-Wunused-variable] int N = n; ^ user.cpp: In function ‘void read()’: user.cpp:10:16: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s + 1); ^ user.cpp: In function ‘int main()’: user.cpp:103:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("csir.in", "r", stdin); ^ user.cpp:104:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("csir.out", "w", stdout); ^ user.cpp:105:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n", &t); ^ /tmp/ccS6JKL4.o: In function `read()': user.cpp:(.text+0x13): warning: the `gets' function is dangerous and should not be used.