[mpich-discuss] warning: assignment makes pointer from integer without a cast

Hello. When 'mpicc'ing' my program, I get these warnings: /media/TOSHIBA/Hooshdaran_p2.c: In function ‘main’: /media/TOSHIBA/Hooshdaran_p2.c:38:5: warning: assignment makes pointer from integer without a cast [enabled by default] /media/TOSHIBA/Hooshdaran_p2.c:39:14: warning: initialization makes pointer from integer without a cast [enabled by default] /media/TOSHIBA/Hooshdaran_p2.c:84:11: warning: assignment makes pointer from integer without a cast [enabled by default] Why are they produced? I attach the program file for you