Compilare: main.cpp: In function 'int main()': main.cpp:41:8: warning: unused variable 'r1' [-Wunused-variable] int r, r1, i; ^~ main.cpp:42:14: warning: unused variable 'mult' [-Wunused-variable] long long j,mult[4][4], a1[4][4], a2[4][4]; ^~~~ main.cpp:43:5: warning: unused variable 'y' [-Wunused-variable] int y; ^ main.cpp:38:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("iepuri.in", "r", stdin); ^ main.cpp:39:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("iepuri.out", "w", stdout); ^ main.cpp:40:15: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&t); ^ main.cpp:45:62: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d %d %d %d %d", &x1, &x2, &x3, &a, &b, &c, &r); ^