triangle.cpp: In function 'int32_t main()':
triangle.cpp:10:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
10 | freopen("triangles.in", "r", stdin ) ;
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
triangle.cpp:11:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
11 | freopen("triangles.out", "w", stdout ) ;
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~