Compilare: main.c:1:1: warning: return type defaults to 'int' [-Wimplicit-int] main(a,b){for(fscanf(fopen("cmmdc.in","r"),"%d%d",&a,&b);b;)b^=a^=b^=a%=b;fprintf(fopen("cmmdc.out","w"),"%d",a^1?a:0);} ^~~~ main.c: In function 'main': main.c:1:1: warning: type of 'a' defaults to 'int' [-Wimplicit-int] main.c:1:1: warning: type of 'b' defaults to 'int' [-Wimplicit-int] main.c:1:15: warning: implicit declaration of function 'fscanf' [-Wimplicit-function-declaration] main(a,b){for(fscanf(fopen("cmmdc.in","r"),"%d%d",&a,&b);b;)b^=a^=b^=a%=b;fprintf(fopen("cmmdc.out","w"),"%d",a^1?a:0);} ^~~~~~ main.c:1:15: warning: incompatible implicit declaration of built-in function 'fscanf' main.c:1:15: note: include '<stdio.h>' or provide a declaration of 'fscanf' main.c:1:22: warning: implicit declaration of function 'fopen' [-Wimplicit-function-declaration] main(a,b){for(fscanf(fopen("cmmdc.in","r"),"%d%d",&a,&b);b;)b^=a^=b^=a%=b;fprintf(fopen("cmmdc.out","w"),"%d",a^1?a:0);} ^~~~~ main.c:1:22: warning: passing argument 1 of 'fscanf' makes pointer from integer without a cast [-Wint-conversion] main.c:1:22: note: expected 'void *' but argument is of type 'int' main.c:1:65: warning: operation on 'a' may be undefined [-Wsequence-point] main(a,b){for(fscanf(fopen("cmmdc.in","r"),"%d%d",&a,&b);b;)b^=a^=b^=a%=b;fprintf(fopen("cmmdc.out","w"),"%d",a^1?a:0);} ^~ main.c:1:62: warning: operation on 'b' may be undefined [-Wsequence-point] main(a,b){for(fscanf(fopen("cmmdc.in","r"),"%d%d",&a,&b);b;)b^=a^=b^=a%=b;fprintf(fopen("cmmdc.out","w"),"%d",a^1?a:0);} ^~ main.c:1:75: warning: implicit declaration of function 'fprintf' [-Wimplicit-function-declaration] main(a,b){for(fscanf(fopen("cmmdc.in","r"),"%d%d",&a,&b);b;)b^=a^=b^=a%=b;fprintf(fopen("cmmdc.out","w"),"%d",a^1?a:0);} ^~~~~~~ main.c:1:75: warning: incompatible implicit declaration of built-in function 'fprintf' main.c:1:75: note: include '<stdio.h>' or provide a declaration of 'fprintf' main.c:1:83: warning: passing argument 1 of 'fprintf' makes pointer from integer without a cast [-Wint-conversion] main(a,b){for(fscanf(fopen("cmmdc.in","r"),"%d%d",&a,&b);b;)b^=a^=b^=a%=b;fprintf(fopen("cmmdc.out","w"),"%d",a^1?a:0);} ^~~~~ main.c:1:83: note: expected 'void *' but argument is of type 'int'