Compilare: main.cpp: In function 'int main()': main.cpp:7:19: warning: unused variable 'exp' [-Wunused-variable] int m,n,i,x,d,exp; ^~~ main.cpp:8:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("exp.in","r",stdin); ^ main.cpp:9:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("exp.out","w",stdout); ^ main.cpp:11:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&m,&n); ^ main.cpp:14:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&x); ^