View Compilation Error

0_0_25095175_8314.c: In function 'main':
0_0_25095175_8314.c:5:9: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
         for(int i=0;a[i]!='\0';i++){
         ^
0_0_25095175_8314.c:5:9: note: use option -std=c99, -std=gnu99, -std=c11 or -std=gnu11 to compile your code