Compilare: main.cpp: In function 'int main()': main.cpp:32:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < q[i].size() ; ++j) ans[q[i][j].second] = s[q[i][j].first]; ~~^~~~~~~~~~~~~ main.cpp:12:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("inversari.in", "r", stdin); ^ main.cpp:13:42: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("inversari.out", "w", stdout); ^ main.cpp:15:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ main.cpp:17:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[i]); ^ main.cpp:27:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^