program to calculate sum of two distances measured in feet and inch using function: #include stdio.h void sum(struct distance d1,struct distance d2); struct distance {     int feet;     int inch; }; void main() {     struct distance d1,d2;     printf("\n Enter the first distance in feet inch format:");     scanf("%d%d",&d1.feet,&d1.inch);     printf("\n Enter the second distance in feet and inch format:");     scanf("%d%d",&d2.feet,&d2.inch);     sum(d1,d2); } void sum(struct distance d1,struct distance d2) {     struct distance d;     d.inch=(d1.inch+d2.inch)%12;     d.feet=d1.feet+d2.feet+(d1.inch+d2.inch)/12;     printf("\n sum of two distances = %dFeet %dInch",d.feet,d.inch); }