Language: C

#include <stdio.h>
#include <string.h>
int main(int argc, char const *argv[]) {
  char S[100];

  scanf("%s",S);
  int b;

  for (int i = 0; i < 100; i++) {
    if(i%2==0){
      if(strcmp(S[i],'R')=!0||strcmp(S[i],'U')=!0||strcmp(S[i],'D')=!0){
        b++;
      }
    }else{
      if(strcmp(S[i],'L')=!0||strcmp(S[i],'U')=!0||strcmp(S[i],'D')=!0){
        b++;
      }
    }
  }

  if(b==0){
    printf("Yes");
  }else{
    printf("No");
  }
  return 0;
}


Compiler output:
main.c: In function 'main':
main.c:11:18: error: passing argument 1 of 'strcmp' makes pointer from integer without a cast [-Wint-conversion]
   11 |       if(strcmp(S[i],'R')=!0||strcmp(S[i],'U')=!0||strcmp(S[i],'D')=!0){
      |                 ~^~~
      |                  |
      |                  char
In file included from main.c:2:
/usr/include/string.h:156:32: note: expected 'const char *' but argument is of type 'char'
  156 | extern int strcmp (const char *__s1, const char *__s2)
      |                    ~~~~~~~~~~~~^~~~
main.c:11:22: error: passing argument 2 of 'strcmp' makes pointer from integer without a cast [-Wint-conversion]
   11 |       if(strcmp(S[i],'R')=!0||strcmp(S[i],'U')=!0||strcmp(S[i],'D')=!0){
      |                      ^~~
      |                      |
      |                      int
/usr/include/string.h:156:50: note: expected 'const char *' but argument is of type 'int'
  156 | extern int strcmp (const char *__s1, const char *__s2)
      |                                      ~~~~~~~~~~~~^~~~
main.c:11:39: error: passing argument 1 of 'strcmp' makes pointer from integer without a cast [-Wint-conversion]
   11 |       if(strcmp(S[i],'R')=!0||strcmp(S[i],'U')=!0||strcmp(S[i],'D')=!0){
      |                                      ~^~~
      |                                       |
      |                                       char
/usr/include/string.h:156:32: note: expected 'const char *' but argument is of type 'char'
  156 | extern int strcmp (const char *__s1, const char *__s2)
      |                    ~~~~~~~~~~~~^~~~
main.c:11:43: error: passing argument 2 of 'strcmp' makes pointer from integer without a cast [-Wint-conversion]
   11 |       if(strcmp(S[i],'R')=!0||strcmp(S[i],'U')=!0||strcmp(S[i],'D')=!0){
      |                                           ^~~
      |                                           |
      |                                           int
/usr/include/string.h:156:50: note: expected 'const char *' but argument is of type 'int'
  156 | extern int strcmp (const char *__s1, const char *__s2)
      |                                      ~~~~~~~~~~~~^~~~
main.c:11:60: error: passing argument 1 of 'strcmp' makes pointer from integer without a cast [-Wint-conversion]
   11 |       if(strcmp(S[i],'R')=!0||strcmp(S[i],'U')=!0||strcmp(S[i],'D')=!0){
      |                                                           ~^~~
      |                                                            |
      |                                                            char
/usr/include/string.h:156:32: note: expected 'const char *' but argument is of type 'char'
  156 | extern int strcmp (const char *__s1, const char *__s2)
      |                    ~~~~~~~~~~~~^~~~
main.c:11:64: error: passing argument 2 of 'strcmp' makes pointer from integer without a cast [-Wint-conversion]
   11 |       if(strcmp(S[i],'R')=!0||strcmp(S[i],'U')=!0||strcmp(S[i],'D')=!0){
      |                                                                ^~~
      |                                                                |
      |                                                                int
/usr/include/string.h:156:50: note: expected 'const char *' but argument is of type 'int'
  156 | extern int strcmp (const char *__s1, const char *__s2)
      |                                      ~~~~~~~~~~~~^~~~
main.c:11:68: error: lvalue required as left operand of assignment
   11 |       if(strcmp(S[i],'R')=!0||strcmp(S[i],'U')=!0||strcmp(S[i],'D')=!0){
      |                                                                    ^
main.c:15:18: error: passing argument 1 of 'strcmp' makes pointer from integer without a cast [-Wint-conversion]
   15 |       if(strcmp(S[i],'L')=!0||strcmp(S[i],'U')=!0||strcmp(S[i],'D')=!0){
      |                 ~^~~
      |                  |
      |                  char
/usr/include/string.h:156:32: note: expected 'const char *' but argument is of type 'char'
  156 | extern int strcmp (const char *__s1, const char *__s2)
      |                    ~~~~~~~~~~~~^~~~
main.c:15:22: error: passing argument 2 of 'strcmp' makes pointer from integer without a cast [-Wint-conversion]
   15 |       if(strcmp(S[i],'L')=!0||strcmp(S[i],'U')=!0||strcmp(S[i],'D')=!0){
      |                      ^~~
      |                      |
      |                      int
/usr/include/string.h:156:50: note: expected 'const char *' but argument is of type 'int'
  156 | extern int strcmp (const char *__s1, const char *__s2)
      |                                      ~~~~~~~~~~~~^~~~
main.c:15:39: error: passing argument 1 of 'strcmp' makes pointer from integer without a cast [-Wint-conversion]
   15 |       if(strcmp(S[i],'L')=!0||strcmp(S[i],'U')=!0||strcmp(S[i],'D')=!0){
      |                                      ~^~~
      |                                       |
      |                                       char
/usr/include/string.h:156:32: note: expected 'const char *' but argument is of type 'char'
  156 | extern int strcmp (const char *__s1, const char *__s2)
      |                    ~~~~~~~~~~~~^~~~
main.c:15:43: error: passing argument 2 of 'strcmp' makes pointer from integer without a cast [-Wint-conversion]
   15 |       if(strcmp(S[i],'L')=!0||strcmp(S[i],'U')=!0||strcmp(S[i],'D')=!0){
      |                                           ^~~
      |                                           |
      |                                           int
/usr/include/string.h:156:50: note: expected 'const char *' but argument is of type 'int'
  156 | extern int strcmp (const char *__s1, const char *__s2)
      |                                      ~~~~~~~~~~~~^~~~
main.c:15:60: error: passing argument 1 of 'strcmp' makes pointer from integer without a cast [-Wint-conversion]
   15 |       if(strcmp(S[i],'L')=!0||strcmp(S[i],'U')=!0||strcmp(S[i],'D')=!0){
      |                                                           ~^~~
      |                                                            |
      |                                                            char
/usr/include/string.h:156:32: note: expected 'const char *' but argument is of type 'char'
  156 | extern int strcmp (const char *__s1, const char *__s2)
      |                    ~~~~~~~~~~~~^~~~
main.c:15:64: error: passing argument 2 of 'strcmp' makes pointer from integer without a cast [-Wint-conversion]
   15 |       if(strcmp(S[i],'L')=!0||strcmp(S[i],'U')=!0||strcmp(S[i],'D')=!0){
      |                                                                ^~~
      |                                                                |
      |                                                                int
/usr/include/string.h:156:50: note: expected 'const char *' but argument is of type 'int'
  156 | extern int strcmp (const char *__s1, const char *__s2)
      |                                      ~~~~~~~~~~~~^~~~
main.c:15:68: error: lvalue required as left operand of assignment
   15 |       if(strcmp(S[i],'L')=!0||strcmp(S[i],'U')=!0||strcmp(S[i],'D')=!0){
      |                                                                    ^