lightningrod.cpp: In function 'int main()':
lightningrod.cpp:14:21: warning: variable 'sum' set but not used [-Wunused-but-set-variable]
14 | int x, y, ret = 0, sum, diff;
| ^~~
lightningrod.cpp:14:26: warning: variable 'diff' set but not used [-Wunused-but-set-variable]
14 | int x, y, ret = 0, sum, diff;
| ^~~~
lightningrod.cpp:21:6: warning: unused variable 'prv' [-Wunused-variable]
21 | int prv = -2e9;
| ^~~
lightningrod.cpp:15:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
15 | scanf("%d", &n);
| ~~~~~^~~~~~~~~~
lightningrod.cpp:17:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
17 | scanf("%d %d", &x, &y);
| ~~~~~^~~~~~~~~~~~~~~~~