Language: C

b,c,d,e,f,t;main(a){for(;~scanf("%d%d%d%d%d%d",&a,&b,&c,&d,&e,&f);printf("%.3f %.3f\n",(c*e-b*f+0.)/t+0.,(a*f-c*d+0.)/t0.))t=a*e-b*d;}

Compiler output:
main.c:1:1: warning: data definition has no type or storage class
    1 | b,c,d,e,f,t;main(a){for(;~scanf("%d%d%d%d%d%d",&a,&b,&c,&d,&e,&f);printf("%.3f %.3f\n",(c*e-b*f+0.)/t+0.,(a*f-c*d+0.)/t0.))t=a*e-b*d;}
      | ^
main.c:1:1: error: type defaults to 'int' in declaration of 'b' [-Wimplicit-int]
main.c:1:3: error: type defaults to 'int' in declaration of 'c' [-Wimplicit-int]
    1 | b,c,d,e,f,t;main(a){for(;~scanf("%d%d%d%d%d%d",&a,&b,&c,&d,&e,&f);printf("%.3f %.3f\n",(c*e-b*f+0.)/t+0.,(a*f-c*d+0.)/t0.))t=a*e-b*d;}
      |   ^
main.c:1:5: error: type defaults to 'int' in declaration of 'd' [-Wimplicit-int]
    1 | b,c,d,e,f,t;main(a){for(;~scanf("%d%d%d%d%d%d",&a,&b,&c,&d,&e,&f);printf("%.3f %.3f\n",(c*e-b*f+0.)/t+0.,(a*f-c*d+0.)/t0.))t=a*e-b*d;}
      |     ^
main.c:1:7: error: type defaults to 'int' in declaration of 'e' [-Wimplicit-int]
    1 | b,c,d,e,f,t;main(a){for(;~scanf("%d%d%d%d%d%d",&a,&b,&c,&d,&e,&f);printf("%.3f %.3f\n",(c*e-b*f+0.)/t+0.,(a*f-c*d+0.)/t0.))t=a*e-b*d;}
      |       ^
main.c:1:9: error: type defaults to 'int' in declaration of 'f' [-Wimplicit-int]
    1 | b,c,d,e,f,t;main(a){for(;~scanf("%d%d%d%d%d%d",&a,&b,&c,&d,&e,&f);printf("%.3f %.3f\n",(c*e-b*f+0.)/t+0.,(a*f-c*d+0.)/t0.))t=a*e-b*d;}
      |         ^
main.c:1:11: error: type defaults to 'int' in declaration of 't' [-Wimplicit-int]
    1 | b,c,d,e,f,t;main(a){for(;~scanf("%d%d%d%d%d%d",&a,&b,&c,&d,&e,&f);printf("%.3f %.3f\n",(c*e-b*f+0.)/t+0.,(a*f-c*d+0.)/t0.))t=a*e-b*d;}
      |           ^
main.c:1:13: error: return type defaults to 'int' [-Wimplicit-int]
    1 | b,c,d,e,f,t;main(a){for(;~scanf("%d%d%d%d%d%d",&a,&b,&c,&d,&e,&f);printf("%.3f %.3f\n",(c*e-b*f+0.)/t+0.,(a*f-c*d+0.)/t0.))t=a*e-b*d;}
      |             ^~~~
main.c: In function 'main':
main.c:1:13: error: type of 'a' defaults to 'int' [-Wimplicit-int]
main.c:1:27: error: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
    1 | b,c,d,e,f,t;main(a){for(;~scanf("%d%d%d%d%d%d",&a,&b,&c,&d,&e,&f);printf("%.3f %.3f\n",(c*e-b*f+0.)/t+0.,(a*f-c*d+0.)/t0.))t=a*e-b*d;}
      |                           ^~~~~
main.c:1:1: note: include '<stdio.h>' or provide a declaration of 'scanf'
  +++ |+#include <stdio.h>
    1 | b,c,d,e,f,t;main(a){for(;~scanf("%d%d%d%d%d%d",&a,&b,&c,&d,&e,&f);printf("%.3f %.3f\n",(c*e-b*f+0.)/t+0.,(a*f-c*d+0.)/t0.))t=a*e-b*d;}
main.c:1:27: warning: incompatible implicit declaration of built-in function 'scanf' [-Wbuiltin-declaration-mismatch]
    1 | b,c,d,e,f,t;main(a){for(;~scanf("%d%d%d%d%d%d",&a,&b,&c,&d,&e,&f);printf("%.3f %.3f\n",(c*e-b*f+0.)/t+0.,(a*f-c*d+0.)/t0.))t=a*e-b*d;}
      |                           ^~~~~
main.c:1:27: note: include '<stdio.h>' or provide a declaration of 'scanf'
main.c:1:67: error: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
    1 | b,c,d,e,f,t;main(a){for(;~scanf("%d%d%d%d%d%d",&a,&b,&c,&d,&e,&f);printf("%.3f %.3f\n",(c*e-b*f+0.)/t+0.,(a*f-c*d+0.)/t0.))t=a*e-b*d;}
      |                                                                   ^~~~~~
main.c:1:67: note: include '<stdio.h>' or provide a declaration of 'printf'
main.c:1:67: warning: incompatible implicit declaration of built-in function 'printf' [-Wbuiltin-declaration-mismatch]
main.c:1:67: note: include '<stdio.h>' or provide a declaration of 'printf'
main.c:1:119: error: 't0' undeclared (first use in this function); did you mean 't'?
    1 | b,c,d,e,f,t;main(a){for(;~scanf("%d%d%d%d%d%d",&a,&b,&c,&d,&e,&f);printf("%.3f %.3f\n",(c*e-b*f+0.)/t+0.,(a*f-c*d+0.)/t0.))t=a*e-b*d;}
      |                                                                                                                       ^~
      |                                                                                                                       t
main.c:1:119: note: each undeclared identifier is reported only once for each function it appears in
main.c:1:122: error: expected identifier before ')' token
    1 | b,c,d,e,f,t;main(a){for(;~scanf("%d%d%d%d%d%d",&a,&b,&c,&d,&e,&f);printf("%.3f %.3f\n",(c*e-b*f+0.)/t+0.,(a*f-c*d+0.)/t0.))t=a*e-b*d;}
      |                                                                                                                          ^