Compilare: main.cpp: In function 'int main()': main.cpp:20:9: warning: left operand of comma operator has no effect [-Wunused-value] c,r=0; ^ main.cpp:7:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] { freopen("pscpld.in", "r",stdin); ^ main.cpp:8:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("pscpld.out", "w",stdout); ^ main.cpp:22:13: warning: 'c' may be used uninitialized in this function [-Wmaybe-uninitialized] ii=2*c-1; ~^~