Language: C

#include<stdio.h>
char a[33];int p(c){return(a[c]>=104&&a[c]<=112)||a[c]==117||a[c]==121?1:0;}main(r,i){for(;gets(a),a[0]!=35;printf("%d\n",r))for(i=r=0;a[i+1];i++)r+=p(i)^p(i+1);exit(0)}

Compiler output:
main.c: In function 'p':
main.c:2:16: error: type of 'c' defaults to 'int' [-Wimplicit-int]
    2 | char a[33];int p(c){return(a[c]>=104&&a[c]<=112)||a[c]==117||a[c]==121?1:0;}main(r,i){for(;gets(a),a[0]!=35;printf("%d\n",r))for(i=r=0;a[i+1];i++)r+=p(i)^p(i+1);exit(0)}
      |                ^
main.c: At top level:
main.c:2:77: error: return type defaults to 'int' [-Wimplicit-int]
    2 | char a[33];int p(c){return(a[c]>=104&&a[c]<=112)||a[c]==117||a[c]==121?1:0;}main(r,i){for(;gets(a),a[0]!=35;printf("%d\n",r))for(i=r=0;a[i+1];i++)r+=p(i)^p(i+1);exit(0)}
      |                                                                             ^~~~
main.c: In function 'main':
main.c:2:77: error: type of 'r' defaults to 'int' [-Wimplicit-int]
main.c:2:77: error: type of 'i' defaults to 'int' [-Wimplicit-int]
main.c:2:92: error: implicit declaration of function 'gets'; did you mean 'fgets'? [-Wimplicit-function-declaration]
    2 | char a[33];int p(c){return(a[c]>=104&&a[c]<=112)||a[c]==117||a[c]==121?1:0;}main(r,i){for(;gets(a),a[0]!=35;printf("%d\n",r))for(i=r=0;a[i+1];i++)r+=p(i)^p(i+1);exit(0)}
      |                                                                                            ^~~~
      |                                                                                            fgets
main.c:2:162: error: implicit declaration of function 'exit' [-Wimplicit-function-declaration]
    2 | char a[33];int p(c){return(a[c]>=104&&a[c]<=112)||a[c]==117||a[c]==121?1:0;}main(r,i){for(;gets(a),a[0]!=35;printf("%d\n",r))for(i=r=0;a[i+1];i++)r+=p(i)^p(i+1);exit(0)}
      |                                                                                                                                                                  ^~~~
main.c:2:1: note: include '<stdlib.h>' or provide a declaration of 'exit'
    1 | #include<stdio.h>
  +++ |+#include <stdlib.h>
    2 | char a[33];int p(c){return(a[c]>=104&&a[c]<=112)||a[c]==117||a[c]==121?1:0;}main(r,i){for(;gets(a),a[0]!=35;printf("%d\n",r))for(i=r=0;a[i+1];i++)r+=p(i)^p(i+1);exit(0)}
main.c:2:162: warning: incompatible implicit declaration of built-in function 'exit' [-Wbuiltin-declaration-mismatch]
    2 | char a[33];int p(c){return(a[c]>=104&&a[c]<=112)||a[c]==117||a[c]==121?1:0;}main(r,i){for(;gets(a),a[0]!=35;printf("%d\n",r))for(i=r=0;a[i+1];i++)r+=p(i)^p(i+1);exit(0)}
      |                                                                                                                                                                  ^~~~
main.c:2:162: note: include '<stdlib.h>' or provide a declaration of 'exit'
main.c:2:169: error: expected ';' before '}' token
    2 | char a[33];int p(c){return(a[c]>=104&&a[c]<=112)||a[c]==117||a[c]==121?1:0;}main(r,i){for(;gets(a),a[0]!=35;printf("%d\n",r))for(i=r=0;a[i+1];i++)r+=p(i)^p(i+1);exit(0)}
      |                                                                                                                                                                         ^
      |                                                                                                                                                                         ;