foo.c:1:9: error: expected '=', ',', ';', 'asm' or '__attribute__' before '<' token
 include <stdio.h> include <stdlib.h> include <string.h>
         ^
foo.c: In function 'main':
foo.c:15:1: warning: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
 scanf("%d%d",&n,&m);
 ^
foo.c:15:1: warning: incompatible implicit declaration of built-in function 'scanf' [enabled by default]
foo.c:17:12: error: 'a' undeclared (first use in this function)
 scanf("%s",a);
            ^
foo.c:17:12: note: each undeclared identifier is reported only once for each function it appears in
foo.c:30:15: error: expected ')' before numeric constant
 a1[i] = (a1[i]10+a[j]-'0')%p1;
               ^
foo.c:31:15: error: expected ')' before numeric constant
 a2[i] = (a2[i]10+a[j]-'0')%p2;
               ^
foo.c:32:15: error: expected ')' before numeric constant
 a3[i] = (a3[i]10+a[j]-'0')%p3;
               ^
foo.c:33:15: error: expected ')' before numeric constant
 a4[i] = (a4[i]10+a[j]-'0')%p4;
               ^
foo.c:55:5: warning: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
     printf("%d\n",ans1);
     ^
foo.c:55:5: warning: incompatible implicit declaration of built-in function 'printf' [enabled by default]
foo.c:59:5: warning: implicit declaration of function 'memset' [-Wimplicit-function-declaration]
     memset(can1,0,sizeof(can1));
     ^
foo.c:59:5: warning: incompatible implicit declaration of built-in function 'memset' [enabled by default]
foo.c:63:22: error: expected expression before '?' token
             s1 = (s1+??a1[i]*tx1)%p1;
                      ^
foo.c:64:27: error: expected expression before ')' token
             tx1 = (tx1*x1?)%p1;
                           ^
foo.c:70:19: error: 'sizeo' undeclared (first use in this function)
     memset(can2,0,sizeo?f(can2));
                   ^
foo.c:70:5: warning: implicit declaration of function 'f' [-Wimplicit-function-declaration]
     memset(can2,0,sizeo?f(can2));
     ^
foo.c:70:32: error: expected ':' before ')' token
     memset(can2,0,sizeo?f(can2));
                                ^
foo.c:71:27: error: expected expression before ')' token
     for (x = 0;x < p2;x?++) {
                           ^
foo.c:82:29: error: expected expression before '?' token
     for (x = 0;x < p3;x++) {??
                             ^
foo.c:84:33: error: expected expression before '?' token
         for (i = 0;i <= n;i++) {??
                                 ^
foo.c:85:35: error: expected ':' before ';' token
             s3 = (s3+a3[i]*tx3)%p3;
                                   ^
foo.c:87:10: error: expected expression before '?' token
         }??
          ^
foo.c:108:5: warning: incompatible implicit declaration of built-in function 'printf' [enabled by default]
     printf("%d\n",ans1);
     ^
foo.c:14:9: warning: unused variable 'k' [-Wunused-variable]
 int i,j,k;
         ^