```
#include <stdio.h> 

int main() { 
    char c = 125; 

    c = c + 10; 

    printf("%d", c); 

    return 0; 
}

```

The output of this code is `-121`.

How this output is `-121`? Can you please explain?

If I add `100` instead of `10` with `c` then output is `-31`.
Why?