foo.cpp:17:5: error: stray '\221' in program
     while(ch<‘0‘||ch>‘9‘){if(ch==‘-‘)f=-1;ch=getchar();}
     ^
foo.cpp:17:5: error: stray '\221' in program
foo.cpp:17:5: error: stray '\221' in program
foo.cpp:17:5: error: stray '\221' in program
foo.cpp:17:5: error: stray '\221' in program
foo.cpp:17:5: error: stray '\221' in program
foo.cpp:18:5: error: stray '\221' in program
     while(ch>=‘0‘&&ch<=‘9‘){x=x*10+ch-‘0‘;ch=getchar();}
     ^
foo.cpp:18:5: error: stray '\221' in program
foo.cpp:18:5: error: stray '\221' in program
foo.cpp:18:5: error: stray '\221' in program
foo.cpp:18:5: error: stray '\221' in program
foo.cpp:18:5: error: stray '\221' in program
foo.cpp: In function 'int read()':
foo.cpp:17:37: error: expected primary-expression before ')' token
     while(ch<‘0‘||ch>‘9‘){if(ch==‘-‘)f=-1;ch=getchar();}
                                     ^