Compilare: main.cpp: In function 'int main()': main.cpp:56:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0 ; j < v[i].size() ; j ++) ~~^~~~~~~~~~~~~ main.cpp:13:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("carte.in" , "r" , stdin); ^ main.cpp:14:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("carte.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" , &tests); ^ main.cpp:18:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%s" , a + 1); ^ main.cpp:19:31: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d" , &nrwords); ^ main.cpp:23:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%s " , b + 1); ^