View Compilation Error

0_0_17644961_2839.c: In function 'main':
0_0_17644961_2839.c:25:17: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
                 for(int i=0;i<step;i++)  
                 ^
0_0_17644961_2839.c:25:17: note: use option -std=c99, -std=gnu99, -std=c11 or -std=gnu11 to compile your code