Answer:
The function in C++ is as follows
int chkInd(string str1, string str2){
int lenstr1=0;
while(str1[lenstr1] != '\0'){ lenstr1++; }
int index = 0; int retIndex=0;
for(int i=lenstr1-1;i>=0; i--){
while (str2[index] != '\0'){
if (str1[i] == str2[index]){
retIndex=1;
break; }
else{ retIndex=0; }
index++; }
if (retIndex == 0){ return i; }else{return -1;}}
}
Explanation:
This defines the function
int chkInd(string str1, string str2){
First, the length of str1 is initialized to 0
int lenstr1=0;
The following loop then calculates the length of str1
while(str1[lenstr1] != '\0'){ lenstr1++; }
This initializes the current index and the returned index to 0
int index = 0; int retIndex=0;
This iterates through str1
for(int i=lenstr1-1;i>=0; i--){
This loop is repeated while there are characters in str2
while (str2[index] != '\0'){
If current element of str2 and str1 are the same
if (str1[i] == str2[index]){
Set the returned index to 1
retIndex=1;
Then exit the loop
break; }
If otherwise, set the returned index to 0
else{ retIndex=0; }
Increase index by 1
index++; }
This returns the calculated returned index; if no matching is found, it returns -1
if (retIndex == 0){ return i; }else{return -1;}}
}