View Compilation Error

0_0_28921008_31477.c:5:12: error: unknown type name 'fir'
 double dis(fir a , fir b){
            ^
0_0_28921008_31477.c:5:20: error: unknown type name 'fir'
 double dis(fir a , fir b){
                    ^
0_0_28921008_31477.c:8:9: error: unknown type name 'fir'
 int min(fir x){
         ^
0_0_28921008_31477.c:20:8: error: unknown type name 'fir'
 int ok(fir x, fir y){
        ^
0_0_28921008_31477.c:20:15: error: unknown type name 'fir'
 int ok(fir x, fir y){
               ^