c++ - Vector comparison with string -

i have string vector of user-input data containing strings. need make sure program won't execute if strings different specified few. vector contains 4 fields , every has different condition:

• vector[0] can "1" or "0"
• vector[1] can "red" or "green
• vector[2] can "1", "2" or "3"
• vector[3] can "1" or "0"

i tried writing if every condition:

if(tokens[0]!="1" || tokens[0]!="0"){     decy = "error"; } else if(tokens[1]!="red" || tokens[1]!="green"){     decy = "error"; } else if(tokens[2]!="1" || tokens[2]!="2" || tokens[2]!="3"){     decy = "error"; } else if(tokens[3]!="1" || tokens[3]!="0"){     decy = "error"; } else{ switch(){} //working code } return decy; 

it enters first if , returns error. tried if instead of else if doesn't work either. checked vector[i] contents , returns correct strings. no " " @ end of etc. removing else , releasing switch makes program check first condition , ignore rest of it.

i'm doing terribly wrong, can't find answer on internet decided ask here.

the conditions invalid.

any distinct value can satisfy conditions.

you should use && instead of ||.

for example:

if (tokens[0] != "1" || tokens[0] != "0") { 

consider line. if tokens[0] "1", valid input, not satisfy first condition, satisfy second. want throw error when value neither of valid possible inputs.

this means condition should be:

if (tokens[0] != "1" && tokens[0] != "0") { 

same goes others.