Compilare: main.cpp: In function 'int main()': main.cpp:10:22: warning: unused variable 'exp' [-Wunused-variable] int m, n, i, x, d, exp; ^~~ main.cpp:12:33: 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:13:35: 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:15:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d", &m, &n); ^ main.cpp:17:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &x); ^