View Compilation Error

0_0_35362077_28103.c: In function 'main':
0_0_35362077_28103.c:19:8: error: 'c' undeclared (first use in this function)
     if(c[i]>='#'&&c[i]<='%'||c[i]=='~'||c[i]=='!'||c[i]=='@'||c[i]=='^')  a4=1;
        ^
0_0_35362077_28103.c:19:8: note: each undeclared identifier is reported only once for each function it appears in