View Compilation Error

0_0_21261282_2001.c: In function 'main':
0_0_21261282_2001.c:8:4: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
    for( int i=1; i<=T; i++ )
    ^
0_0_21261282_2001.c:8:4: note: use option -std=c99, -std=gnu99, -std=c11 or -std=gnu11 to compile your code
0_0_21261282_2001.c:14:9: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
         for( int j=1;j<=40000;j++ )
         ^
0_0_21261282_2001.c:20:18: error: redefinition of 'j'
         for( int j=0;j<n; j++ )
                  ^
0_0_21261282_2001.c:14:18: note: previous definition of 'j' was here
         for( int j=1;j<=40000;j++ )
                  ^
0_0_21261282_2001.c:20:9: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
         for( int j=0;j<n; j++ )
         ^