/in/foo.c: In function 'main':
/in/foo.c:21:15: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
  if (year%4==0&&year%100!=0||year%400==0)
      ~~~~~~~~~^~~~~~~~~~~~~
/in/foo.c:63:128: warning: statement with no effect [-Wunused-value]
     day10=day+month_day[0]+month_day[1]+month_day[2]+month_day[3]+month_day[4]+month_day[5]+month_day[6]+month_day[7];month_day[8];
                                                                                                                       ~~~~~~~~~^~~
/in/foo.c:67:131: warning: statement with no effect [-Wunused-value]
     day11=day+month_day[0]+month_day[1]+month_day[2]+month_day[3]+month_day[4]+month_day[5]+month_day[6]+month_day[7];month_day[8]+month_day[9];
                                                                                                                       ~~~~~~~~~~~~^~~~~~~~~~~~~
/in/foo.c:71:144: warning: statement with no effect [-Wunused-value]
     day12=day+month_day[0]+month_day[1]+month_day[2]+month_day[3]+month_day[4]+month_day[5]+month_day[6]+month_day[7];month_day[8]+month_day[9]+month_day[10];
                                                                                                                       ~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~
/in/foo.c:118:128: warning: statement with no effect [-Wunused-value]
     day10=day+month_day[0]+month_day[1]+month_day[2]+month_day[3]+month_day[4]+month_day[5]+month_day[6]+month_day[7];month_day[8];
                                                                                                                       ~~~~~~~~~^~~
/in/foo.c:122:131: warning: statement with no effect [-Wunused-value]
     day11=day+month_day[0]+month_day[1]+month_day[2]+month_day[3]+month_day[4]+month_day[5]+month_day[6]+month_day[7];month_day[8]+month_day[9];
                                                                                                                       ~~~~~~~~~~~~^~~~~~~~~~~~~
/in/foo.c:126:144: warning: statement with no effect [-Wunused-value]
     day12=day+month_day[0]+month_day[1]+month_day[2]+month_day[3]+month_day[4]+month_day[5]+month_day[6]+month_day[7];month_day[8]+month_day[9]+month_day[10];
                                                                                                                       ~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~