View Compilation Error

0_0_31921549_29524.c: In function 'main':
0_0_31921549_29524.c:9:9: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
         for(int x=m;x<=n;x++)
         ^
0_0_31921549_29524.c:9:9: note: use option -std=c99, -std=gnu99, -std=c11 or -std=gnu11 to compile your code
0_0_31921549_29524.c:20:6: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
      for(int j=0;j<a-1;j++){
      ^
0_0_31921549_29524.c:25:5: error: expected declaration or statement at end of input
     return 0;
     ^