foo.cc: In function 'int main()':
foo.cc:8:33: warning: conversion from 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} to 'unsigned int' changes value from '18446744073709551615' to '4294967295' [-Woverflow]
    8 |     const unsigned int no = str.npos;
      |                                 ^~~~
foo.cc:10:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   10 |     scanf("%d%d",&n,&m);
      |     ~~~~~^~~~~~~~~~~~~~

正在同步测试数据，请稍后
ENOSPC: no space left on device, write
Error: ENOSPC: no space left on device, write
undefined
[Hydro](https://hydro.ac)提供评测服务