Language: C

f(X){for(;c<X;c+=v[p++]);c=100*(c-X);}
n,v[50],s,p,c;main(){for(;n=atoi(gets(v));printf("%d\n",s)){for(p=s=0;p<n;v[++p]=strlen(gets(v+n)));for(;c;p=++s)c=0,f(5),f(7),f(5),f(7),f(7);}}

Compiler output:
main.c:1:1: error: return type defaults to 'int' [-Wimplicit-int]
    1 | f(X){for(;c<X;c+=v[p++]);c=100*(c-X);}
      | ^
main.c: In function 'f':
main.c:1:1: error: type of 'X' defaults to 'int' [-Wimplicit-int]
main.c:1:11: error: 'c' undeclared (first use in this function)
    1 | f(X){for(;c<X;c+=v[p++]);c=100*(c-X);}
      |           ^
main.c:1:11: note: each undeclared identifier is reported only once for each function it appears in
main.c:1:18: error: 'v' undeclared (first use in this function)
    1 | f(X){for(;c<X;c+=v[p++]);c=100*(c-X);}
      |                  ^
main.c:1:20: error: 'p' undeclared (first use in this function)
    1 | f(X){for(;c<X;c+=v[p++]);c=100*(c-X);}
      |                    ^
main.c: At top level:
main.c:2:1: warning: data definition has no type or storage class
    2 | n,v[50],s,p,c;main(){for(;n=atoi(gets(v));printf("%d\n",s)){for(p=s=0;p<n;v[++p]=strlen(gets(v+n)));for(;c;p=++s)c=0,f(5),f(7),f(5),f(7),f(7);}}
      | ^
main.c:2:1: error: type defaults to 'int' in declaration of 'n' [-Wimplicit-int]
main.c:2:3: error: type defaults to 'int' in declaration of 'v' [-Wimplicit-int]
    2 | n,v[50],s,p,c;main(){for(;n=atoi(gets(v));printf("%d\n",s)){for(p=s=0;p<n;v[++p]=strlen(gets(v+n)));for(;c;p=++s)c=0,f(5),f(7),f(5),f(7),f(7);}}
      |   ^
main.c:2:9: error: type defaults to 'int' in declaration of 's' [-Wimplicit-int]
    2 | n,v[50],s,p,c;main(){for(;n=atoi(gets(v));printf("%d\n",s)){for(p=s=0;p<n;v[++p]=strlen(gets(v+n)));for(;c;p=++s)c=0,f(5),f(7),f(5),f(7),f(7);}}
      |         ^
main.c:2:11: error: type defaults to 'int' in declaration of 'p' [-Wimplicit-int]
    2 | n,v[50],s,p,c;main(){for(;n=atoi(gets(v));printf("%d\n",s)){for(p=s=0;p<n;v[++p]=strlen(gets(v+n)));for(;c;p=++s)c=0,f(5),f(7),f(5),f(7),f(7);}}
      |           ^
main.c:2:13: error: type defaults to 'int' in declaration of 'c' [-Wimplicit-int]
    2 | n,v[50],s,p,c;main(){for(;n=atoi(gets(v));printf("%d\n",s)){for(p=s=0;p<n;v[++p]=strlen(gets(v+n)));for(;c;p=++s)c=0,f(5),f(7),f(5),f(7),f(7);}}
      |             ^
main.c:2:15: error: return type defaults to 'int' [-Wimplicit-int]
    2 | n,v[50],s,p,c;main(){for(;n=atoi(gets(v));printf("%d\n",s)){for(p=s=0;p<n;v[++p]=strlen(gets(v+n)));for(;c;p=++s)c=0,f(5),f(7),f(5),f(7),f(7);}}
      |               ^~~~
main.c: In function 'main':
main.c:2:29: error: implicit declaration of function 'atoi' [-Wimplicit-function-declaration]
    2 | n,v[50],s,p,c;main(){for(;n=atoi(gets(v));printf("%d\n",s)){for(p=s=0;p<n;v[++p]=strlen(gets(v+n)));for(;c;p=++s)c=0,f(5),f(7),f(5),f(7),f(7);}}
      |                             ^~~~
main.c:2:34: error: implicit declaration of function 'gets' [-Wimplicit-function-declaration]
    2 | n,v[50],s,p,c;main(){for(;n=atoi(gets(v));printf("%d\n",s)){for(p=s=0;p<n;v[++p]=strlen(gets(v+n)));for(;c;p=++s)c=0,f(5),f(7),f(5),f(7),f(7);}}
      |                                  ^~~~
main.c:2:43: error: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
    2 | n,v[50],s,p,c;main(){for(;n=atoi(gets(v));printf("%d\n",s)){for(p=s=0;p<n;v[++p]=strlen(gets(v+n)));for(;c;p=++s)c=0,f(5),f(7),f(5),f(7),f(7);}}
      |                                           ^~~~~~
main.c:1:1: note: include '<stdio.h>' or provide a declaration of 'printf'
  +++ |+#include <stdio.h>
    1 | f(X){for(;c<X;c+=v[p++]);c=100*(c-X);}
main.c:2:43: warning: incompatible implicit declaration of built-in function 'printf' [-Wbuiltin-declaration-mismatch]
    2 | n,v[50],s,p,c;main(){for(;n=atoi(gets(v));printf("%d\n",s)){for(p=s=0;p<n;v[++p]=strlen(gets(v+n)));for(;c;p=++s)c=0,f(5),f(7),f(5),f(7),f(7);}}
      |                                           ^~~~~~
main.c:2:43: note: include '<stdio.h>' or provide a declaration of 'printf'
main.c:2:82: error: implicit declaration of function 'strlen' [-Wimplicit-function-declaration]
    2 | n,v[50],s,p,c;main(){for(;n=atoi(gets(v));printf("%d\n",s)){for(p=s=0;p<n;v[++p]=strlen(gets(v+n)));for(;c;p=++s)c=0,f(5),f(7),f(5),f(7),f(7);}}
      |                                                                                  ^~~~~~
main.c:1:1: note: include '<string.h>' or provide a declaration of 'strlen'
  +++ |+#include <string.h>
    1 | f(X){for(;c<X;c+=v[p++]);c=100*(c-X);}
main.c:2:82: warning: incompatible implicit declaration of built-in function 'strlen' [-Wbuiltin-declaration-mismatch]
    2 | n,v[50],s,p,c;main(){for(;n=atoi(gets(v));printf("%d\n",s)){for(p=s=0;p<n;v[++p]=strlen(gets(v+n)));for(;c;p=++s)c=0,f(5),f(7),f(5),f(7),f(7);}}
      |                                                                                  ^~~~~~
main.c:2:82: note: include '<string.h>' or provide a declaration of 'strlen'
main.c:2:89: error: passing argument 1 of 'strlen' makes pointer from integer without a cast [-Wint-conversion]
    2 | n,v[50],s,p,c;main(){for(;n=atoi(gets(v));printf("%d\n",s)){for(p=s=0;p<n;v[++p]=strlen(gets(v+n)));for(;c;p=++s)c=0,f(5),f(7),f(5),f(7),f(7);}}
      |                                                                                         ^~~~~~~~~
      |                                                                                         |
      |                                                                                         int
main.c:2:89: note: expected 'const char *' but argument is of type 'int'